Dr. Ramkumar Venkatachalam

Dr. V.Ramkumar

Research Topics

1. Ionic liquids
2. In-situ cryo crystallization of ionic liquids
3. Polymorphism in APIs and their crystal structure

Contact: vramkumar@bce.au.dk

 

A Ph.D from Indian Institute of Technology Madras, India and having 18 years of experience in solving crystal structures of organic and inorganic compounds with complex disorders such as solvent, residue, and twinning.  Experience in analyzing ionic liquids by in-situ cryo-crystallization technique and computational studies.

Analyzed and refined over 8000 crystal structures, assisted various institutions and industries in India. Published over 185 research articles in prominent international journals, having one US patent and 4 Indian patents.  Possess a strong analytical skills and proficient in various instrumentation techniques and like GC-MS, TGA, DSC, FTIR, and MS.

In Feb, 2024 joined the vibrant group of Prof. Anja V. Mudring as post doc at Aarhus University, which is known for its excellence, innovation, and collaboration research initiatives.

LIST OF PUBLICATIONS 

185. Mayank G Sharma, Ruturajsinh M Vala, Dhanji P Rajani, Venkatachalam Ramkumar, Ramesh L. Gardas, Sourav Banerjee, Hitendra M Patel, Crystal structure, antibacterial and antifungal evaluation of 5-bromothiophene based 3,4-dihydropyrimidin-2-(1H)-(thi)ones, Phosphorus Sulfur Silicon Relat. Elem., 2023, 198 (2), 145-153. 1080/10426507.2022.2121397

184. Venkatachalam Ramkumar, Ramesh L Gardas, Structural Arrangements of Guanidinium-Based Dicarboxylic Acid Ionic Liquids and Insights into Carbon Dioxide Uptake through Structural Voids, Growth Des., 2022, 22 (6), 3646-3655. doi.org/10.1021/acs.cgd.1c01360

183. Subham G Patel, Ruturajsinh M Vala, Paras J Patel, Dipti B Upadhyay, V Ramkumar, Ramesh L Gardas, Hitendra M Patel, Synthesis, crystal structure and in silico studies of novel 2, 4-dimethoxy-tetrahydropyrimido [4, 5-b] quinolin-6 (7 H)-ones, RSC adv., 2022, 12 (29), 18806-18820. org/10.1039/D2RA02694E

182. Venkatachalam Ramkumar, Ramesh L Gardas, Exploring the solvation behavior of guanidinium based carboxylate ionic liquids in DMSO and DMF through apparent molar properties, Mol. Liq., 2021, 343, 117664. doi.org/10.1016/j.molliq.2021.117664

181. S Pappuru, V Ramkumar, D Chakraborty, Benzoxazole phenoxide ligand supported group IV catalysts and their application for the ring‐opening polymerization of rac‐lactide and ε‐caprolactone, Polymers Adv. Tech., 2021, 32 (9), 3392-3401. org/10.1002/pat.5349

180. Mayank G Sharma, Juhee Pandya, Divyang M Patel, Ruturajsinh M Vala, V. Ramkumar, Raghunandankumar Subramanian, Vivek K Gupta, Ramesh L Gardas, Anuradha Dhanasekaran, Hitendra M Patel, One-Pot assembly for synthesis of 1, 4-dihydropyridine scaffold and their biological applications, Polycycl. Aromat. Compd., 2021, 41 (7), 1495-1505. doi.org/10.1080/10406638.2019.1686401

179. Venkatachalam Ramkumar, Ramesh Gardas, Sourav Banerjee, Hitendra Patel, Mayank Sharma, Ruturajsinh Vala, Dhanji Rajani, Crystal structure and Biological evolution of 5-bromothiophene based 3, 4-dihydropyrimidin-2-(1H)-thi (ones), Research Square, 2021. org/10.21203/rs.3.rs-721141/v1

178. S. Gomosta, S. Kar, A.N. Pradhan, S. Bairagi, V. Ramkumar, S. Ghosh, Synthesis, Structures, and Bonding of Metal-Rich Metallaboranes Comprising Triply Bridging Borylene and Boride Moieties, Organometallics, 2021, 40 (4), 529-538. doi.org/10.1021/acs.organomet.0c00780

177. S.K Roymuhury, M. Mandal, D. Chakraborty, V. Ramkumar, Homoleptic titanium and zirconium complexes exhibiting unusual O iminol–metal coordination: application in stereoselective ring-opening polymerization of lactide, Polymer Chem.,2021, 12 (27), 3953-3967. doi.org/10.1039/D1PY00237F

176. R. M. Vala, M.G. Sharma, D. M. Patel, Adrián Puerta, José M Padrón, V. Ramkumar, Ramesh L. Gardas, H. M. Patel, Synthesis and in vitro study of antiproliferative benzyloxy dihydropyrimidinones, Archiv der Pharmazie, 2021, 354 (6), 2000466. doi.org/10.1002/ardp.202000466

175. Jais Kurian, Kanneth S Shurooque, Venkatachalam Ramkumar, Lakshmi Chakkumkumarath, Muraleedharan Kannoth M, Delocalization Effects and Tunable Emission in a Class of Charged Cyclazines with Nitrogen on the Periphery, Lett. 2021, 23, 9, 3354–3358. doi.org/10.1021/acs.orglett.1c00827.

174. Suman Gomosta, Sourav Kar, Alaka Nanda Pradhan, Subhash Bairagi, Venkatachalam Ramkumar, Sundargopal GhoshSynthesis, Structures, and Bonding of Metal-Rich Metallaboranes Comprising Triply Bridging Borylene and Boride Moieties, Organometallics, 2019, 40 (4), 529-538. org/10.1021/acs.organomet.0c00780

173. M. G. Sharma, J. Pandya, D. M. Patel, R. M. Vala, V. Ramkumar, R. Subramanian, Vivek K Gupta, Ramesh L. Gardas, Anuradha Dhanasekaran, H. M. Patel, One-Pot assembly for synthesis of 1, 4-dihydropyridine scaffold and their biological applications, Polycycl. Aromat. Compd., 2019, 1-11. doi.org10.1080/10406638.2019.1686401

172. M. Somasundaram, Jai Anand Garg, Shivaji Naidu, V. Ramkumar, R. Saiganesh, S. Kabilan, K. K. Balasubramanian, Halogen-Exchange Fluorination of beta-Chlorovinyl Aldehydes-Unexpected Cascade Transformations in the Fluorination of 4-Chloro-2H-chromene and 4-Chloro-2H-thiochromene-3, Eur. J. Org. Chem., 2019, (36), 6269-6277. doi.org/10.1002/ejoc.201901069

171. V Ramkumar, RL Gardas, Thermophysical Properties and Carbon Dioxide Absorption Studies of Guanidinium-Based Carboxylate Ionic Liquids, Chem. Engg. Data, 2019, 64 (11), 4844-4855. doi.org/10.1021/acs.jced.9b00377

170. S. K. Kushvaha, S. Arumugam, B. Shankar, R. S. Sarkar, V. Ramkumar, K. C. Mondal, Isolation and Characterization of Different Homometallic and Heterobimetallic Complexes of Nickel and Zinc Ions by Controlling Molar Ratios and Solvents, Eur. J. Inorg. Chem. 2019 (24), 2871-2882. doi.org/10.1002/ejic.201900338

169. V. Ramkumar, Indrajit Das, Ramesh L Gardas, Structural Arrangement and Computational Exploration of Guanidinium Based Ionic Liquids with Benzoic Acid Derivatives as Anion, Cryst. Growth Des., 2019, 19, 2642-2657. doi.org/10.1021/acs.cgd.8b01754

168. Nisha Chetty, V. Ramkumar, Narasimha N Murthy, Bis-and mono-tridentate chelated iron complexes with a new facially capping unsymmetrical nitrogen ligand: X-ray structural and spectroscopic studies, Polyhedron, 2019, 158, 241-247. doi.org/10.1016/j.poly.2018.09.008.

167. Mrinmay Mandal, V. Ramkumar, Debashis Chakraborty, Salen complexes of zirconium and hafnium: Synthesis, structural characterization and polymerization studies, Polym. Chem., 2019 10, 3444-3460. doi.org/10.1039/C8PY01750F

166. Moulika Bhattacharyya, Kuppusamy Yuvaraj, Alokananda Chanda, Venkatachalam Ramkumar, Sundargopal Ghosh, Metal‐Rich Metallaboranes: Structures and Geometries of Heterometallic µ9‐Boride Clusters, J. Inorg.Chem., 2018, 22, 2574-2583. doi.org/10.1002/ejic.201800375

165. Attoor Chandrasekhar, Venkatachalam Ramkumar, Sethuraman Sankararaman, Palladium catalyzed carbonylative annulation of the C (sp₂)–H bond of N, 1-diaryl-1 H-tetrazol-5­amines and N, 4-diaryl-4 H-triazol-3-amines to quinazolinones, biomol. Chem., 2018, 18, 8629-8638. doi.org/10.1039/C8OB02516A

164. Mayank G. Sharma, Ruturajsinh M. Vala, Divyang M. Patel, Irene Lagunes, Miguel X Fernandes, José M Padrón, Venkatachalam Ramkumar, Ramesh L Gardas, Hitendra M Patel, Anti‐Proliferative 1, 4‐Dihydropyridine and Pyridine Derivatives Synthesized through a Catalyst‐Free, One‐Pot Multi‐Component Reaction, Select, 2018, 3, 12163-12168. doi.org/10.1002/slct.201802537

163. J. B. Shaik, V. Ramkumar, S. Sankararaman, Synthesis of a new class of cationic Pd (II) complexes with 1, 2, 3-triazol-5-ylidene ligand and their catalytic application in the conversion of internal alkynes to 1, 2-diketones. J. Organomet. Chem. 2018, 860, 1-8. doi.org/10.1016/j.jorganchem.2018.02.011

162. D. Chakraborty, B. Rajashekhar, M. Mandal, V. Ramkumar, Group 4 metal complexes containing the salalen ligands: Synthesis, structural characterization and studies on the ROP of cyclic esters, J. Organomet. Chem., 2018, 871, 111-121. doi.org/10.1016/j.jorganchem.2018.03.035

161. M. G. Chowdhury, S. K. Barik, K. Saha, B. Kirubakaran, Abhishek Banerjee, Venkatachalam Ramkumar, Sundargopal Ghosh, Electron Precise Group 5 Dimetallaheteroboranes, Chem., 2018, 57, 985–994. doi.org/10.1021/acs.inorgchem.7b02305.

160. B. Rajashekhar, M. Mandal, D. Chakraborty, V. Ramkumar, Homoleptic Zr and Hf Complexes of Imino/Bis (imino) phenoxide Scaffolds: Synthesis, structural characterization and their catalytic activity in the ROP of cyclic ester, Chem. Select, 2017, 2, 8408-8417. doi.org/10.1002/slct.201701602.

159. I. Das, B. kumar Chennuri, V. Ramkumar, R L. Gardas , Understanding the solvation behavior of tetramethylguanidinium based ionic liquids in dilute aqueous solutions through apparent molar properties, J. Mol. Liq., 2017, 242, 129-136. doi.org/10.1016/j.molliq.2017.07.006

158. K. V. Ramanaiah, V. Ramkumar, N. N. Murthy, High-spin iron (II) complexes of halides and pseudo-halides with biphenyl-appended N, N’-bidentate ligand: X-ray structural and spectroscopic studies, Inorg. Chim. Acta, 2017, 466, 197-204. doi.org/10.1016/j.ica.2017.06.013

 

157. S. Pappuru, D. Chakraborty, V. Ramkumar, D. K. Chand, Ring-opening co polymerization of maleic anhydride or L-Lactide with tert-butyl glycidyl ether by using efficient Ti and Zr benzoxazole-substituted 8-Hydroxyquinolina, Polymer, 2017, 123, 267-281. doi.org/10.1016/j.polymer.2017.06.073

156. H. Behera, V. Ramkumar, N. Madhavan, Triamide macrocyclic chloride receptors via a one-pot tandem reduction–condensation–cyclization reaction, Org. biomol. chem., 2017, 15, 4937-4940. doi.org/10.1039/C7OB00642J

155. D. Sasi, V. Ramkumar, N. N. Murthy, Bite-Angle-Regulated Coordination Geometries: Tetrahedral and Trigonal Bipyramidal in Ni (II) with Biphenyl-Appended (2-Pyridyl) alkylamine N, N’-Bidentate Ligand, ACS Omega, 2017, 2 (6), 2474-2481. doi.org/10.1021/acsomega.7b00119

154. E. Varadharajan, V. Ramkumar, M. V. B. Scholastica, A. P. T. Augustine, 3-Benzylidene -1′-methyl-4′-phenyldispiro [cyclopentane-1, 3′-pyrrolidine-2′, 1”-acenaphthene]-2, 2”­dione, IUCrData, 2017, 2 (4), x170581. doi.org/10.1107/S2414314617005818

153. S.V. Raghava, P. Gopinath, B. K. Srivastava, V. Ramkumar, Sulfamide-Lattice Restructuring to Form Dimensionally Controlled Molecular Arrays and Gel-Forming Systems, Chem. Eur. J., 2017, 23, 3658-3665. doi.org/10.1002/chem.201604911

152. S.Pappuru, D. Chakraborty, V. Ramkumar, Nb and Ta benzotriazole or benzoxazole phenoxide complexes as catalysts for the ring-opening polymerization of glycidol to synthesize hyperbranched polyglycerols, Dalton Trans., 2017, 46, 16640-16654. doi.org/10.1039/C7DT02839C

151. Sheelam, S. Mandal, T. Thippani, V. Ramkumar, K. Ramanujam, Carbon-supported Co (III) dimer for oxygen reduction reaction in alkaline medium, Ionics, 2016, 22, 2183-2194. doi.org/10.1007/s11581-016-1730-1.

150. S. Pappuru, D. Chakraborty, J. V. Sundar, S. K. Roymuhury, V. Ramkumar, Group 4 complexes of salicylbenzoxazole ligands as effective catalysts for the ring-opening polymerization of lactides, epoxides and copolymerization of e-caprolact, Polymer, 2016, 102, 231-247. doi.org/10.1016/j.polymer.2016.08.007

149. D. Chakraborty, E. R. Chokkapu, M. Mandal, R. R. Gowda, V. Ramkumar, Zwitterionic Complexes of Group 4 Metal Chlorides Containing a Bis (imino) phenoxide Scaffold: Synthesis, Characterization and Polymerization Studies, Chem. Select, 2016, 1, 5218-5229. doi.org/10.1002/slct.201600909.

148. A. Dasgupta, V. Ramkumar, S. Sankararaman, Synthesis of Fluorescent 1, 3-Diaryl propynones by Carbonylative Alkynylation Reaction Using (Phosphine)(1, 2, 3-triazol-5­ylidene) palladium Complexes as Catalyst, Eur. J. Org. Chem., 2016, 28, 4817-4823. doi.org/10.1002/ejoc.201600744.

147. A. Chandrasekhar, V. Ramkumar, S. Sankararaman, Highly Selective and Modular Synthesis of 3-Aryl-4-(arylethynyl)-2H-chromen-2-ones from 2-Iodoaryl 2-Arylacetates through a carbonylative Sonogashira Coupling, Eur. J. Org. Chem., 2016, 23, 4041-4049. doi.org/10.1002/ejoc.201600569.

146. K. Yuvaraj, M. Bhattacharyya, R. Prakash, V. Ramkumar, S. Ghosh, New Trinuclear Complexes of Group 6, 8, and 9 Metals with a Triply Bridging Borylene Ligand, Chem. Eur. J., 2016, 22 , 8889-8896. doi.org/10.1002/chem.201600637

145. S. K. Roymuhury, D. Chakraborty, V. Ramkumar, Zwitterionic niobium and tantalum complexes with bidentate aminophenol scaffolds: synthesis, structural characterization and use in the ring opening polymerization, RSC Adv., 2016, 6 (54), 48816-48826. doi.org/10.1039/C6RA09789H

144. B. Sureshbabu, V. Ramkumar, S. Sankararaman, A mild and efficient method for the synthesis of structurally diverse 1, 2, 3-triazolylidene palladium (II) diiodo complexes. Comparison of catalytic activities for Suzuki–Miyaura coupling, J. Organomet. Chem., 2015, 799, 232-238. doi.org/10.1016/j.jorganchem.2015.10.002

143. A. Mohan, V. Ramkumar, S. Sankararaman, Synthesis and structures of (-) menthyl and (+) neomenthyl substituted enantio pure bis (1, 2, 3-triazol-5-ylidene) PdI₂ complexes and PEPPSI type (1, 2, 3-triazol-ylidene) (pyridine)PdI₂complexes. Comparison of catalytic activities for C–C coupling), J. Organomet. Chem., 2015, 799, 115-121. doi.org/10.1016/j.jorganchem.2015.09.019

142. D. K. Roy, R. Borthakur, S. Bhattacharyya, V. Ramkumar, S. Ghosh, Borate-based ligands with soft heterocycles and their ruthenium complexes, J. Organomet. Chem., 2015, 799, 132-137. doi.org/10.1016/j.jorganchem.2015.07.036.

141. S. K. Roymuhury, D. Chakraborty, V. Ramkumar, Aluminium complexes bearing N, O­aminophenol ligands as efficient catalysts for the ring opening polymerization of lactide, Euro.Polymer J., 2015, 70, 203-214. doi.org/10.1016/j.eurpolymj.2015.07.025.

140. H. Behera, V. Ramkumar, N. Madhavan, Cation-Transporting Peptides: Scaffolds for Functionalized Pores? Chem. Euro. J., 2015, 21, 10179-10184. doi.org/10.1002/chem.201500881.

139. S. Ghosh, D. Chakraborty, V. Ramkumar, Imino (phenoxide) compounds of magnesium: Synthesis, structural characterization, and polymerization studies, J. Poly. Sci. Part A: Poly. Chem., 2015, 53, 1474-1491. doi.org/10.1002/pola.27579.

138. M. C. Naranthatta, V. Ramkumar, D. K. Chand, Role of peripheral phenanthroline groups in the self-assembly of self-assembled molecular triangles, J. Chem. Sci., 2015, 127, 273-280. doi.org/10.1007/s12039-015-0776-3.

137. R. Vaidyanathaswamy, G. A. Raman, V. Ramkumar, R. Anand, Nucleophilic difluoro alkylation of benzophenones, benzaldehydes and Schiff’s bases by tetrafluoroethyl ether and difluoroacetamide, J. Fluor. Chem., 2015, 169, 38-49. doi.org/10.1016/j.jfluchem.2014.11.001.

136. D. Chakraborty, D. Mandal, V. Ramkumar, V. Subramanian, J. V. Sundar, A new class of MPV type reduction in group 4 alkoxide complexes of salicylaldiminato ligands: Efficient catalysts for the ROP of lactides, epoxides and polymerization, Polymer, 2015, 56, 157-170. doi.org/10.1016/j.polymer.2014.10.074

135. B. Rajashekhar, S. K. Roymuhury, D. Chakraborty, V. Ramkumar, Group 4 metal complexes of Trost’s semi-crown ligand: synthesis, structural characterization and studies on the ring-opening polymerization of lactides and e-caprola, Dalton Trans, 2014, 44, 16280-16293. doi.org/10.1039/C5DT02267C

134. S. K. Roymuhury, D. Chakraborty, V. Ramkumar, Synthesis and characterization of group 4 metal alkoxide complexes containing imine based bis-bidentate ligands: effective catalysts for the ring opening polymerization, Dalton Trans., 2014, 44, 10352-10367. doi.org/10.1039/C5DT01092F

133. S. K. Roymuhury, D. Chakraborty, V. Ramkumar, Zwitterionic group 4 aminophenolate catalysts for the polymerization of lactides and ethylene, New J. Chem., 2015, 39, 5218-5230. doi.org/10.1039/C5NJ00486A.

132. M. Mandal, D. Chakraborty, V. Ramkumar, Zr (iv) complexes containing salan-type ligands: synthesis, structural characterization and role as catalysts towards the polymerization of e-caprolactone, rac-lactide, RSC Adv., 2015, 5, 28536-28553. doi.org/10.1039/c4ra17201a

131. A. Dasgupta, V. Ramkumar, S. Sankararaman, Catalytic asymmetric hydrogenation using a [2.2] paracyclophane based chiral 1, 2, 3-triazol-5-ylidene–Pd complex under ambient conditions and 1 atmosphere of H₂, RSC Adv., 2015, 5, 21558-21561. doi.org/10.1039/C5RA03021H.

130. P. Bhyrappa, U. K. Sarangi, V. Velkannan, V. Ramkumar, ß-Tetrasubstituted meso-Tetra (4′-n-butylphenyl) porphyrins and Their Metal Complexes: Synthesis and Structural Properties, Euro J. Inorg. Chem. 2014, 33, 5760-5770. doi.org/10.1002/ejic.201402661.

129. D. H. Park, V. Ramkumar, P. Parthiban, Crystal structure of 2, 4-bis (2-chlorophenyl)-7­tert-pentyl-3-azabicyclo [3.3. 1] nonan-9-one, Acta Cryst., 2014, E 70, o1161-o1162. doi.org/10.1107/S160053681402176X

128. D. H. Park, V. Ramkumar, P. Parthiban, Crystal structure of 2,6-bis­­(2,5-di­meth­­oxy­phen­yl)-3,5-di­methyl­piperidin-4-one, Acta Cryst., 2014, E 70, o1160. doi.org/10.1107/S1600536814022041

127. V. P. Anju, S. K. Barik, B. Mondal, V. Ramkumar, S. Ghosh, Metallaboranes from Metal Carbonyl Compounds and Their Utilization as Catalysts for Alkyne Cyclotrimerization, ChemPlusChem, 2014, 79, 546-551. doi.org/10.1002/cplu.201400013

126. V. Karthikeyan, V. Ramkumar, R. J. Karunakaran, 1′-Allyl-1-(3, 4-dimethylbenzoyl)-2­(4-methyl-1, 3-thiazol-5-yl)-1, 2, 5, 6, 7, 7a-hexahydrospiro [pyrrolizine-3, 3′-indolin]-2’­one, Acta Cryst, 2014, E70 (5), o541-o542. doi.org/10.1107/S1600536814006990

125. Sandip Guchhait , Keshab Ghosh, B. Sureshbabu, V. Ramkumar, S. Sankararaman, C2­Symmetric normal and mesoionic bis-N-heterocyclic carbenes with biphenyl backbone. A comparison of bis (1, 2, 3-triazol-5-ylidene) and bis (imidazol-2-ylidene) ligands, J. Organomet. Chem., 2014, 768, 68–74. doi.org/10.1016/j.jorganchem.2014.06.023.

124. A. Pati, J. Athilakshmi, V. Ramkumar, D. K. Chand, Two dimensional polydodecameric water-chloride cluster enfolding (Hg-Cl-Hg)+ concealed cascade cryptate, CrystEngComm., 2014, 16, 6827-6830. (2014). doi.org/10.1039/C4CE00802B.

123. B. Sureshbabu, V. Ramkumar, S. Sankararaman, Facile base-free in situ generation and palladation of mesoionic and normal N-heterocyclic carbenes at ambient conditions, Dalton Trans., 2014, 43, 10710-10712. doi.org/10.1039/C4DT01112K

122. S. Bandi, N. B. Debata, V. Ramkumar, D. K. Chand, One-pot synthesis of self-assembled heteroleptic palladium (II) complexes with tmeda: An application of ligand exchange reactions, Inorg. Chem. Commun., 2014, 39, 75-78. doi.org/10.1016/j.inoche.2013.10.047.

121. R. Ramachandran, G. Prakash, S. Selvamurugan, P. Viswanathamurthi, Jan Grzegorz Malecki and V. Ramkumar, Efficient and versatile catalysis of N-alkylation of heterocyclic amines with alcohols and one-pot synthesis of 2-aryl substituted benzazoles with newly designed ruthenium (ii) complexes of PNS thiosemicarbazones, Dalton Trans., 2014, 43, 7889-7902. . doi.org/10.1039/C4DT00006D

120. L. Sahoo, A. Singhamahapatra, V. Ramkumar, D. Loganathan, Regioselective opening of unsymmetrical cyclic anhydrides: synthesis of N-glycosylated isoasparagine and isoglutamine conjugates, RSC Adv., 2014, 4, 22042-22047. doi.org/10.1039/C4RA01234H

119. B. Sureshbabu, V. Ramkumar, S. Sankararaman, Substituent effect on the formation of helical to layered hydrogen bond networks in hydroxyl and carboxyl substituted 1-aryl-1 H-1, 2, 3- triazoles, CrystEngComm., 2014, 16, 6098-6106. doi.org/10.1039/C4CE00738G.

118. M. Mathiselvam, V. Ramkumar, D. Loganathan, S. Pérez, Effect of distal sugars and interglycosidic linkage on the N-glycoprotein linkage region conformation: synthesis and X-Ray crystallographic investigation of ß-1-N-alkanamide derivatives of cellobiose and maltose as disaccharide analogs of the conserved chitobiosylasparagine linkage, Glycoconjugate J., 2014, 31, 71-87. doi.org/10.1007/s10719-013-9504-8

117. R. Deepan Chakravarthy, V. Ramkumar and D. Kumar Chand, A molybdenum based metallomicellar catalyst for controlled and selective sulfoxidation reactions in aqueous medium, Green Chem., 2014, 16, 2190-2196. doi.org/10.1039/C3GC42245C

116. D. Tripathy, H. S. Sahoo, V. Ramkumar, D. K. Chand, Palladium (ii) induced complete conformational enrichment of the syn isomer of N, N’-bis (4-pyridylformyl) piperazine, RSC Adv., 2014, 4, 18595-18599. org/10.1039/C3RA47904H.

115. K. Senthil, S. Kalainathan, A. RubanKumar, V. Ramkumar, J Podder, 2-[(E)-2-(4­Methoxyphenyl) ethenyl]-1-methylpyridinium iodide, Acta Cryst., 2013, E 69, o1848­o1848. doi.org/10.1107/S1600536813031929

114. S. Pappuru, E. R. Chokkapu, D. Chakraborty, V. Ramkumar, Group IV complexes containing the benzotriazole phenoxide ligand as catalysts for the ring-opening polymerization of lactides, epoxides and as precatalysts for the polymerization of ethylene, Dalton Trans., 2013, 42, 16412-16427. doi.org/10.1039/c3dt52065j

113. P. Niranjana, A. Pati, S. K. Porwal, V. Ramkumar, S.J. Gharpure, D.K. Chand, Coordination polymers via self-assembly of silver (i) and cis-bis-nitrile-oxa-bowl derivatives, CrystEngComm, 2013, 15, 9623-9633. doi.org/10.1039/c3ce41003j

112. S. H. A. Lakshmi, M. Kandaswamy and V. Ramkumar, 2,2′-{[(1E,1’E) – (Cyclohexane­1,4-diyl) bis(azanylylidene)] bis(ethan-1-yl-1-ylidene)}diphenol, Acta Cryst., 2013, E69, o1593. doi.org/10.1107/S1600536813026123

111. M. G. Meera, P. K. Selvaraj, B. Viswanathan and V. Ramkumar, [mu]-(2,6-Bis{[3­(dimethylamino)propyl] iminomethyl}-4-methylphenolato)-[mu]-hydroxido­bis[(thiocyanato-[kappa]N) copper (II)], Acta Cryst., 2013, E69, m542-543. doi.org/10.1107/S1600536813024768

110. V. Karthikeyan, V. Ramkumar and R. J. Karunakaran , Ethyl 2-amino-4-(4-methyl-1,3­thiazol-5-yl)-5-oxo-4H,5H-pyrano[3,2-c]chromene-3-carboxylate, Acta Cryst., 2013, E69, o1411-o1412. doi.org/10.1107/S1600536813021703

109. D. H. Park, Ramkumar, P. Parthiban (1E, 4E)-1, 5-Bis [2-(trifluoromethyl) phenyl] penta-1, 4-dien-3-one, Acta Cryst., 2013, E 69 (2), o177. doi.org/10.1107/S1600536812051586

108. D. H. Park,V. Ramkumar, P. Parthiban, 2, 4, 6, 8-Tetrakis (2-fluorophenyl)-3, 7­diazabicyclo [3.3. 1] nonan-9-one, Acta Cryst., 2013, E 69 (2), o179. doi.org/10.1107/S1600536812051574

107. T. K. Saha, M. Mandal, D. Chakraborty, V. Ramkumar, Imino phenoxide complexes of group 4 metals: synthesis, structural characterization and polymerization studies, New J. Chem., 2013, 37, 949-960. doi.org/10.1039/c3nj40916c.

106. Saha, Tanmoy Kumar., Mandal, Mrinmay., Thunga, Madhubabu., Chakraborty, Debashis., Ramkumar, Venkatachalam., Imino phenoxide complexes of niobium and tantalum as catalysts for the polymerization of lactides, a-caprolactone and ethylene, Dalton Trans., 2013, 42, 10304-10314. org/10.1039/C3DT50752A

105. R. Ganesamoorthi, A. Thakur, D. Sharmila, V. Ramkumar, S. Ghosh, Synthesis and characterization of N-phenyl pyrrole anchored to Fischer carbene complex through ring closing metathesis oxidative aromatization and various aryl substituted Fischer carbene complexes, J. Organomet. Chem., 2013, 726, 56-61. doi.org/10.1016/j.jorganchem.2012.12.014.

104. R. S. Anju, D. K. Roy, B. Mondal, V. Ramkumar, S. Ghosh, An Early-Late Transition Metal Hybrid Analog of Hexaborane(12): Organometallics., 2013, 32, 4618-4623. doi.org/10.1021/om400594d.

103. K. Yuvaraj, D. K. Roy, K. Geetharani, B. Mondal, V. P. Anju, P. Shankhari, V. Ramkumar, S. Ghosh., Chemistry of Homo-and Heterometallic Bridged-Borylene Complexes. Organometallics, 2013, 32 (9), 2705-2712. doi.org/10.1021/om400167f

102. J. B. Shaik, V. Ramkumar, B. Varghese, S. Sankararaman, Synthesis and structure of trans-bis (1, 4-dimesityl-3-methyl-1, 2, 3-triazol-5-ylidene) palladium (II) dichloride and diacetate. Suzuki–Miyaura coupling of polybromoarenes with high catalytic turnover efficiencies, Beilstein J. Org. Chem., 2013, 9, 698-704. doi.org/10.3762/bjoc.9.79.

101. R.Saravanakumar, V. Ramkumar, S. Sankararaman, Synthesis and Structural Characterization of cis Isomer of 1, 2, 3-Triazol-5-ylidene based Palladium Complexes, J. Organomet. Chem., 2013, 736, 36-41. doi.org/10.1016/j.jorganchem.2013.03.008.

100. Roy, Dipak Kumar., Bose, Shubhankar Kumar., Anju, R. S., Mondal, Bijan., Ramkumar, V., Ghosh, Sundargopal., Boron Beyond the Icosahedral Barrier: A 16­Vertex Metallaborane, Chem. Int. Ed. Engl., 2013, 52, 3222-3226. doi.org/10.1002/ange.201208849

99. D. Tripathy, V. Ramkumar, D. K. Chand, Toppled Molecular Domino Sets by Self-Assembly of Self-assembly: The p-Polymers, Cryst. Growth Des., 2013, 13(8), 3763-3772. doi.org/10.1021/cg400781x.

98. K. K. Chakrahari, A. Thakur, B. Mondal, V. Ramkumar, S. Ghosh, Hypoelectronic dimetallahetero boranes of Group 6 Transition Metals Containing Heavier Chalcogen Elements, Inorg. Chem., 2013, 52, 7923-7932. doi.org/10.1021/ic400432v

97. N. Haridharan, V. Ramkumar, 1, 3-Bis (2-methylprop-2-enoyl)-1H-benzimidazol-2 (3H)-one, Acta Cryst., 2013, E 69 (6), o818. doi.org/10.1107/S1600536813011380

96. Park, Dong Ho., Ramkumar, V., Parthiban, P., 2,4-Bis(4-ethoxyphenyl)-1-methyl-3­azabicyclo[3.3.1]nonan-9-one, Acta Cryst., 2012, E 68, o2999. org/10.1107/S1600536812039840

95. Park, Dong Ho., Ramkumar, V., Parthiban, P., 2,4-Bis(4-ethoxyphenyl)-3­azabicyclo[3.3.1]nonan-9-one, Acta Cryst., 2012, E 68, o2841. org/10.1107/S1600536812037385

94. Park, Dong Ho., Ramkumar, V., Parthiban, P., 2,4-Bis(2-bromophenyl)-7-tert-pentyl­3-azabicyclo[3.3.1]nonan-9-one, Acta Cryst., 2012, E 68, o2946. org/10.1107/S1600536812039128

93. Park, Dong Ho., Ramkumar, V., Parthiban, P., 2,6-Bis(4-chlorophenyl)-1,3­dimethylpiperidin-4-one O-benzyloxime, Acta Cryst., 2012, E 68, o525. org/10.1107/S1600536812002152

92. Park, Dong Ho., Ramkumar, V., Parthiban, P., 2,6-Bis(4-methoxyphenyl)-1,3­dimethylpiperidin-4-one O-benzyloxime, Acta Cryst., 2012, E 68, o524. org/10.1107/S1600536812002140

91. A. Doddi, J. V. Kingston, V. Ramkumar, M. Suzuki, M. Hojo, M. N. S. Rao,Synthesis and Characterization of Dianionic Hexacoordinate Silicon (IV) Complexes of Substituted Catechols, Flavones, and Fluorone: X-Ray Crystal Structures of [(n-C₃H₇) ₂NH₂]₂ [(Cl₄C₆O₂)₃Si]₃ CH₃CN and [(n-C₃H₇)₂NH₂]₂ [(Br₄C₆O₂)₃Si]₂ (CH₃)₂SO, Phosphorus, Sulfur, and Silicon and the Relat. Elem., 2012, 187 (3), 343-356. doi.org/10.1080/10426507.2011.613078

90. Thakur, Arunabha., Sao, Soumik., Ramkumar,V., Ghosh, Sundargopal., Novel Class of Heterometallic Cubane and Boride Clusters Containing Heavier Group 16 Elements, Chem., 2012, 51, 8322-8330. doi.org/10.1021/ic3008602

89. Park, Dong Ho., Ramkumar, V., Parthiban, P., 2,4-Bis(2-ethoxyphenyl)-3­zabicyclo[3.3.1]nonan-9-one, Acta Cryst., 2012, E 68, o3282. org/10.1107/S1600536812044856

88. Geetharani, K., Ramkumar, V., Ghosh, Sundargopal., Synthesis and Characterization of Novel Ruthenaferracarboranes from Photoinsertion of Alkynes into a Ruthenaferraborane, Organometallics, 2012, 31, 6381-6387. org/10.1021/om300607u

87. Park, Dong Ho., Ramkumar, V., Parthiban, P., 2,4,6,8-Tetrakis(4-chlorophenyl)-3,7­diazabicyclo [3.3.1] nonan-9-one O-benzyloxime acetone monosolvate, Acta Cryst., 2012, E 68, o1481-o1481. org/10.1107/S1600536812016509

86. Chakrahari, Kiran Kumar Varma., Thakur, Arunabha., Mondal, Bijan., Dhayal, Rajendra Singh., Ramkumar, V., Ghosh, Sundargopal., A close-packed boron-rich 11-vertex molybdaborane with novel geometry, Organomet. Chem., 2012, 710, 75-79. doi.org/10.1016/j.jorganchem.2012.02.027

85. Haridharan, N., Ramkumar, V., Dhamodharan, R., N, N’-(1,4-Phenylene) bis (2-bromo-2­methylpropanamide), Acta Cryst., 2012, E 68, o811. org/10.1107/S1600536812003479

84. Naranthatta, Mili C., Das, Deepika., Tripathy, Debakanta., Sahoo, Himansu S., Ramkumar, Venkatachalam., Chand, Dillip K., Consequence of Presence and Absence of Ã-Clouds at Strategic Locations of Designed Binuclear Pd (II) Complexes on Packing: Self-Assembly of Self-Assembly by Intermolecular Locking and Packing, Growth Des., 2012, 12, 6012-6022. doi.org/10.1021/cg301085t

83. Roy, Bose., Shubhankar Kumar, Anju, R. S., Ramkumar, V., Ghosh, Sundargopal., Synthesis and Structure of Dirhodium Analogue of Octaborane-12 and Decaborane­14, Chem., 2012, 51, 10715-10722. doi.org/10.1021/ic301070e

82. D. H. Park, V. Ramkumar and P. Parthiban, 2,4,6,8-Tetrakis(4-chlorophenyl)-3,7­diazabicyclo [3.3.1]nonan-9-one O-benzyloxime acetone monosolvate, Acta Cryst., 2012, E68, o1481. doi.org/10.1107/S1600536812016509.

81. D. H. Park, V. Ramkumar and P. Parthiban, 2,4-Bis(4-ethoxyphenyl)-7-methyl-3­azabicyclo [3.3.1] nonan-9-one, Acta Cryst., 2012, E68, o779-o780. doi.org/10.1107/S1600536812006563

80. N. Haridharan, V. Ramkumar and R. Dhamodharan, N, N’-(1,4-Phenylene) bis (2-bromo­2-methylpropanamide), Acta Cryst., 2012, E68, o811. doi.org/10.1107/S1600536812003479

79. D. H. Park, V. Ramkumar and P. Parthiban, 2,6-Bis(4-chlorophenyl)-1,3­dimethylpiperidin-4-one O-benzyloxime, Acta Cryst., 2012, E68, o525. doi.org/10.1107/S1600536812002152

78. D. H. Park, V. Ramkumar and P. Parthiban, 2,6-Bis(4-methoxyphenyl)-1,3­dimethylpiperidin-4-one O-benzyloxime, Acta Cryst., 2012, E68, o524. doi.org/10.1107/S1600536812002140

77. D. H. Park, V. Ramkumar and P. Parthiban, 2,4-Bis(4-ethoxyphenyl)-3-azabicyclo [3.3.1] nonan-9-one, Acta Cryst., 2012, E68, o2841. doi.org/10.1107/S1600536812037385

76. D. H. Park, V. Ramkumar and P. Parthiban, 2,4-Bis(2-bromophenyl)-7-tert-pentyl-3­azabicyclo [3.3.1] nonan-9-one, Acta Cryst., 2012, E68, o2946. doi.org/10.1107/S1600536812039128

75. Ravikumar R. Gowda, Debashis Chakraborty, Venkatachalam Ramkumar, Controlled Hydrolysis of [Ti(O–2,4,6-Br₃C₆H₂)₂(O-iPr)₂]₂: synthesis, structural characterization and studies on bulk polymerization of cyclic esters and lactide, Chem. Commun., 2011, 14, 1777-1782. doi.org/10.1016/j.inoche.2011.08.008

74. Ravikumar R Gowda, Venkatachalam Ramkumar and Debashis Chakraborty, 1,1’­binaphthyl-2,2′-diyl benzylphosphoramidate, Acta Cryst., 2011, E67(12), o3310. org/10.1107/S1600536811046861

73. D. H. Park, V. Ramkumar and P. Parthiban, 2,4-Bis (4-ethoxyphenyl) -1-methyl -3­azabicyclo [3.3.1]nonan-9-one, Acta Cryst., 2011, E68, o2999. doi.org/10.1107/S1600536812039840

72. N.Haridharan, V. Ramkumar and R. Dhamodharan, 3-(9H-Carbazol-9-yl)propan-1­ol, Acta Cryst., 2011, E67(1), o180. doi.org/10.1107/S1600536810051809

71. Rajan Deepan Chakravarthy, Kotapati Suresh, Venkatachalam Ramkumar and Dillip Kumar Chand, New Chiral Molybdenum Complex Catalyzed Sulfide Oxidation with Hydrogen Peroxide, Inorganica Chim. Acta, 2011, 376, 57-63. org/10.1016/j.ica.2011.05.033

70. Rajendra Singh Dhayal, V. Ramkumar, Sundargopal Ghosh, Synthesis, Structure and Characterization of Dimolybdaheteroboranes, Polyhedron, 2011, 30 (12), 2062-2066. doi.org/10.1016/j.poly.2011.05.013.

69. P. Parthiban, V. Ramkumar and Y. T. Jeong, 2,4-Bis(4-propoxyphenyl) -3-azabicyclo [3.3.1] nonan-9-one, Acta Cryst., 2011, E67(4), o790. doi.org/10.1107/S1600536811007483

68. Tanmoy kumar saha, Venkatachalam Ramkumar and Debashis Chakraborty, Salen Complexes of Zirconium and Hafnium: Synthesis, Structural Characterization, Controlled Hydrolysis, and Solvent-Free Ring-Opening Polymerization of Cyclic Esters and Lactides, Chem., 2011, 50, 2720-2722. doi.org/10.1021/ic1025262

67. P. Parthiban, V. Ramkumar and Y. T. Jeong, 2,4-Bis (4-butoxyphenyl) -3-azabicyclo [3.3.1] nonan-9-one, Acta Cryst., 2011, E67(3), o635. doi.org/10.1107/S1600536811005058.

66. Rajendran Saravanakumar, Venkatachalam Ramkumar and Sethuraman Sankararaman, Synthesis and Structure of 1,4-Diphenyl-3-methyl-1,2,3-triazol-5-ylidene Palladium Complexes and Application in Catalytic Hydroarylation of Alkynes, Organometallics, 2011, 30, 1689-1694. org/10.1021/om1011984.

65. Niladri B. Debata, V. Ramkumar and Dillip Kumar Chand, A model study of alternative approach toward a class of palladium (II) based self-assembly, Inorg. Chim. Acta, 2011, 372, 71-78. doi.org/10.1016/j.ica.2011.02.009

64. M. Kannan, V. Ramkumar and R. Dhamodharan, Acta Cryst., 2011, E67, o3352, org/10.1107/S1600536811046873

63. Ravikumar R. Gowda, Debashis Chakraborty, Venkatachalam Ramkumar, Aryloxy and benzyloxy compounds of zirconium: synthesis, structural characterization and studies on solvent-free ring opening polymerization of e-caprolactone and d-valerolactone, Organomet. Chem., 2011, 696, 572-580. doi.org/10.1016/j.jorganchem.2010.09.026

62. P. Parthiban, V. Ramkumar, Dong Ho Park and Y. T. Jeong, 2,4-Bis(2-ethoxyphenyl)-7­methyl-3-azabicyclo [3.3.1] nonan-9-one, Acta Cryst., 2011, E67(6), o1475-o1476. doi.org/10.1107/S1600536811018472

61. Ravikumar R. Gowda, Debashis Chakraborty, Venkatachalam Ramkumar, Phosphoroamidate compounds of 1,1′-Bi-2-naphthol: Synthesis, structural characterization and solvent-free ring-opening polymerization of e-caprolactone and L­lactide, Chimi. Acta., 2011, 372, 88-93. doi.org/10.1016/j.ica.2011.01.088

60. Vaibhave Aggarwal, V. Ram Kumar and Udai P. Singh, Synthesis and Molecular Structure of Sulfur Containing Cobalt Compounds, J. Chem. Cryst., 2011, 41, 121-126. doi.org/10.1007/s10870-010-9849-9

59. T.Augustine, Scholastica Mary Vithiya, S. Ignacimuthu and V. Ramkumar, 3-Benzoyl-1­methyl-4-phenylspiro-[acenaphthylene-1(2H),2-pyrrolidin]-2-one, Acta Cryst., 2010, E66, o3002. doi.org/10.1107/S160053681004376X.

58. P. Parthiban, V. Ramkumar and Y. T. Jeong, 2,4-Bis(2-methylphenyl)-3-azabicyclo- ­ [3.3.1]nonan-9-one O-methyloxime. Acta Cryst., 2010, E66, o2978. doi.org/10.1107/S1600536810043436

57. Kasipandi Vellaisamy, John Victor Napoleon, Ramkumar Venkatachalam and Muraleedharan Kannoth Manheri, Multi-chelation approach towards natural product-like skeletons: one-pot access to a nitrogen-containing tetracyclic framework from AlaAla dipeptide, Commun., 2010, 46, 9212-9214. doi.org/10.1039/C0CC03355C.

56. Ravikumar R Gowda, Venkatachalam Ramkumar and Debashis Chakraborty, p- Tolylmethanaminium cyclohexane-1,2-diyl phosphate, Acta Cryst., 2010, E66(12), o3049. org/10.1107/S1600536810044326

55. Paramasivam Parthiban, Senthamaraikannan Kabilan, Venkatachalam Ramkumar, Yeon Tae Jeong, Stereocontrolled facile synthesis and antimicrobial activity of oximes and oxime ethers of diversely substituted bispidines, Med. Chem. Lett., 2010, 20, 6452­6458. doi.org/10.1016/j.bmcl.2010.09.079

54. Neelamegan Haridharan, Venkatachalam Ramkumar, Raghavachari Dhamodharan, Exploration of Novel Pyrene Labeled Amphiphilic Block Copolymers: Synthesis Via ATRP, Characterization and Properties, Macro. Sci., Part A, 2010, 47, 918 -926. doi.org/10.1080/10601325.2010.501681

53. N. Haridharan, V. Ramkumar and R. Dhamodharan, 2-Bromo-2-methyl-N-(4-methyl-2­oxo-2H-chromen-7-yl)propanamide, Acta Cryst., 2010, E66, o2007. doi.org/10.1107/S1600536810026802

52. M. Kannan, V. Ramkumar and R. Dhamodharan, 2,4,6-Trimethyl-3,5-bis [(phenyl carbono thioyl) sulfanyl methyl] benzyl benzenecarbodithioate, Acta Cryst., 2010, E66, o1382. doi.org/10.1107/S1600536810016028

51. Niladri B. Debata, Debakanta Tripathy, V. Ramkumar, Dillip Kumar Chand, Coordination driven self-assembly in a single pot, Tetrahedron Lett., 2010, 51, (33), 4449-4451. doi.org/10.1016/j.tetlet.2010.06.084.

50. Ravikumar R. Gowda, Debashis Chakraborty, Venkatachalam Ramkumar, Aryloxy and benzyloxy compounds of hafnium: Synthesis, structural characterization and studies on solvent-free ring-opening polymerization of e-caprolactone and d-valerolactone, Polymer, 2010, 51, 4750-4759. org/10.1016/j.polymer.2010.08.031

49. Malik, P., Chakraborty, D., Ramkumar, V., New Phosphoroamidate compounds: Synthesis, structural characterization and studies of ZnCl2 assisted hydrolysis of the P-N bond. Polyhedron, 2010, 29, 2142-2148. org/10.1016/j.poly.2010.04.002

48. Paul, S. S. Punnoose, N. L. Mary, T. Narasimhaswamy and V. Ramkumar, (N1E, N2E) ­N1, N2-Bis(4-hexyloxy-3-methoxybenzylidene) ethane-1,2-diamine, Acta Cryst., 2010, E66, o1377. doi.org/10.1107/S1600536810017125

47. N. Haridharan, V. Ramkumar and R. Dhamodharan, 2-Oxo-4-trifluoromethyl-2H­chromen-7-yl 2-bromo-2-methylpropanoate. Acta Cryst., 2010, E66, o1606. doi.org/10.1107/S1600536810020234

46. R. R. Gowda, V. Ramkumar and D. Chakraborty, Triethylammonium 1,1′-binaphthyl­2,2′-diyl phosphate, Acta Cryst., 2010, E66, o1625. doi.org/10.1107/S160053681002026X

45. Rajeswari, S., Venkatesa Prabhu, G., Tamilvendan, D., V. Ramkumar, Spectroscopic studies and crystal structure of 1-(morpholino (phenyl) methyl) pyrrolidine-2,5-dione. J. Chem. Cryst., 2010, 40, 437-442. doi.org/10.1007/s10870-009-9674-1

44. Balamurugan, D., Ramkumar, V., Muraleedharan, K.M., Trans – ß 2,3-amino acid-based supramolecular synthons for probing the interrelationships between structures, torsion-directed assembly and isomorphism, Growth Des., 2010, 10, 2460-2464. doi.org/10.1021/cg100208m

43. Saha, T.K., Rajashekhar, B., Gowda, R.R., Ramkumar, V., Chakraborty, D., Bis (imino) phenoxide complexes of zirconium: Synthesis, structural characterization and solvent ­free ring-opening polymerization of cyclic esters and lactides, Dalton Trans., 2010, 39, 5091-5093 org/10.1039/C002875D.

42. P. Parthiban, V. Ramkumar and Y. T. Jeong , 2,4-Bis(4-chlorophenyl)-1-methyl-3-aza bicyclo [3.3.1]nonan-9-one, Acta Cryst., 2010, E66, o545. doi.org/10.1107/S1600536810004095

41. P. Parthiban, V. Ramkumar and Y. T. Jeong , 2,4-Bis(2-fluorophenyl)-1-methyl-3-aza bicyclo [3.3.1]nonan-9-one, Acta Cryst., 2010, E66, o194-o195. doi.org/10.1107/S1600536809053677

40. Bose, S.K., Geetharani. K, Ramkumar V., Varghese. B., Ghosh, Sundargopal, Chemistry of Vanadaboranes: Synthesis, Structures and Charanterization of Organ vanadium Sulfide Clusters with Disulfido linkage, Inorg.Chem., 2010, 49, 2881-2888. doi.org/10.1021/ic9023597

39. Paramasivam Parthiban, Paramasivam Rathika, Venkatachalam Ramkumar, Se Mo Son, Yen Tae Jeong, Stereospecific synthesisof oximes and oxime ethers of 3-azabicycles: A SAR study towards antimicrobial agents, Med. Chem. Lett., 2010, 20, 1642-1647. doi.org/10.1016/j.bmcl.2010.01.048

38. P. Parthiban, V. Ramkumar and Y. T. Jeong, 2,4-Bis(3-methoxyphenyl)-3-azabicyclo [3.3.1] nonan-9-one. Acta Cryst., 2010, E66, o48-o49. doi.org/10.1107/S1600536809050697

37. Thakur, A., Chakraborty, A., Ramkumar, V., Ghosh, Sundargopal, A new synthetic route to Lindqvist type clusters [(n-Bu₄N)_x][M’M₅O₁₉] [when x = 2, M’= M = Mo or W; x = 3, M’= Mo, M = W] from metal carbonyl precursors [(CO)₅ML] [M = Mo, W; L= CO, C(OMe)(Me)], Dalton Trans., 2009, 36, 7552-7558. org/10.1039/B908348K

36. Pushparathinam Gopinath, Surapaneni Nilaya , Tripathy Ranjan Debi , Venkatachalam Ramkumar and Kannoth Manheri Muraleedharan, As many as six tandem reactions in one step! Unprecedented formation of highly functionalized benzothiophenes, Commun., 2009, 46, 7131-7133. doi.org/10.1039/B914424B

35. Paramasivam Parthiban, Gopalakrishnan Aridoss, Paramasivam Rathika, Venkatachalam Ramkumar, Senthamaraikannan Kabilan, Synthesis, stereochemistry and antimicrobial studies of novel oxime ethers of aza/diazabicycles, Med. Chem. Lett., 2009, 19, 6981-6985. doi.org/10.1016/j.bmcl.2009.10.042.

34. Bose, S.K., Geetharani, K, Ramkumar V., Mobin, S. K., Ghosh, Sundargopal, Fine-Tunning of Metalloborane Geometries: Chemistry of Metallaboranes of Early Transistion Metals derived from Metal halides and Monoborane reagents, Chem. Eur. J., 2009, 15, 13483-13490. doi.org/10.1002/chem.200901819.

33. P. Parthiban, V. Ramkumar and Y. T. Jeong, 2,4-Bis(2-fluorophenyl)-3-azabicyclo [3.3.1] nonan-9-one. Acta Cryst., 2009, E65, o1596. doi.org/10.1107/S1600536809022065

32. P. Parthiban, V. Ramkumar and Y. T. Jeong ,1-Methyl-2,4-Bis(2-methoxyphenyl)-3­azabicyclo [3.3.1] nonan-9-one. Acta Cryst., 2009, E65, o3103. doi.org/10.1107/S1600536809047928

31. Augustine A.P.T., Charles C. Kanakam., Scholastica Mary vithiy and V. Ramkumar, A facile entry into a novel class of dispiroheterocyclic framework through 1, 3­dipolarcycloaddition of azomethine ylides with 3-arylidene-4-chromanones as dipolarophiles. Tetrahedron Lett., 2009, 50, 5906-5909. doi.org/10.1016/j.tetlet.2009.08.010

30. Sahoo, S., Reddy. K. H. K., Dhayal, R. S., Mobin, S. K., Ramkumar, V., Jemmis, E. D., Ghosh, Sundargopal, Chlorinated Hypoelectronic Dimetallaborane Clusters: Synthesis, Characterization and Electronic Structures of (5-C₅Me₅W)₂B₅H_nCl_m (n=7, m=2 and n=8, m=1), Chem., 2009, 48, 6509–6516. doi.org/10.1021/ic900467d

29. Ravikumar R. Gowda, Debashis Chakraborty, Venkatachalam Ramkumar, New Aryloxy and Benzyloxy Derivatives of Titanium as Catalysts for Bulk Ring-Opening Polymerization of ϵ-Caprolactone and δ-Valerolactone, J. Inorg. Chem., 2009, 20, 2981-2993. doi.org/10.1002/ejic.200900280

28. Paramasivam Parthiban, Gopalakrishnan Aridoss, Paramasivam Rathika, Venkatachalam Ramkumar and Senthamaraikannan Kabilan. Synthesis, spectral, crystal and antimicrobial studies of biologically potent oxime ethers of nitrogen, oxygen and sulfur heterocycles. Med. Chem. Lett., 2009, 19, 2981–2985. doi.org/10.1016/j.bmcl.2009.04.038

27. Geetharani, K., Bose, S. K., Pramanik, G., Saha, T. K., Ramkumar, V., Ghosh, Sundargopal An Efficient Route to Group 6 and 8 Metallaborane Compounds: Synthesis of arachno- [Cp*Fe (CO)B3H8] and closo-[(Cp*M)₂B₅H₉] (M = Mo, W), J. Inorg. Chem., 2009,11, 1483-1487. doi.org/10.1002/ejic.200801137

26. Dhayal, R. S., Chakrahari, K. K. V., Ramkumar, V., Ghosh, Sundargopal, β-Alkylation and Arylation of (ç₅-C₅Me₅Mo)₂B₅H₉: Synthesis and Characterization of Isomeric (e₅­C₅Me₅Mo)₂B₅H₉-nR_n (When R=n-Bu, n=2, 1; R=Ph, n=2, 1), Cluster Sci., 2009, 20, 565 –572. doi.org/10.1007/s10876-009-0258-1

25. P. Parthiban, V. Ramkumar, M. S. Kim, S. Kabilan and Y. T. Jeong ,2,4-Bis (4-chloro phenyl)-3-azabicyclo [3.3.1] nonan-9-one, Acta Cryst., 2009, E65, o609. doi.org/10.1107/S160053680900590X

24. P. Parthiban, V. Ramkumar, H. D. Santan, J. T. Kim and Y. T. Jeong, 2,4-Bis (3-chloro phenyl)-3-azabicyclo [3.3.1] nonan-9-one., Acta Cryst, 2009, E65, o840. doi.org/10.1107/S1600536809009945.

23. P. Parthiban, V. Ramkumar, M. S. Kim, S. M. Son and Y. T. Jeong, 2,4-Bis (2-methoxy phenyl)-3-azabicyclo [3.3.1] nonan-9-one, Acta Cryst., 2009, E65, o1383. doi.org/10.1107/S1600536809018686

22. P. Parthiban, V. Ramkumar, S. Amirthaganesan and Y. T. Jeong, 2,4-Bis(4­bromophenyl)-3-azabicyclo [3.3.1] nonan-9-one, Acta Cryst., 2009, E65, o1356. doi.org/10.1107/S1600536809017565

21. Rajeswari. S, Venkatesa Prabhu. G, Tamilvendan. D, V. Ramkumar Spectroscopic studies and crystal structure of 1- [(2,5-dioxopyrrolidin-1-yl) (phenyl) methyl] thio urea, J. Chem. Cryst., 2009, 39, 650–654. doi.org/10.1007/s10870-009-9538-8

20. Rajendra S. Dhayal, Satyanarayan Sahoo, V. Ramkumar and Sundargopal Ghosh, Substitution at Boron in Molybdaborane Frameworks: Synthesis and Characterization of Isomeric (h₅-C₅Me₅Mo)₂ B₅H_nX_m (when X=Cl: n=5, 7, 8; m=4, 2, 1 and X=Me: n=6,7; m=3,2), J. Organomet. Chem., 2009, 694, 237-243. doi.org/10.1016/j.jorganchem.2008.10.036

19. L. Muruganandam, S. Rajeswari, D. Tamilvendan, V. Ramkumar and G. V. Prabhu N ­[Morpholino (phenyl)methyl] benzamide, Acta Cryst., 2009, E65, o578. doi.org/10.1107/S1600536809005327

18. T. Augustine, Scholastica Mary Vithiya, V. Ramkumar and Charles C. Kanakam, 3­Benzylidene-6-methoxychroman-4-one, Acta Cryst., 2008, E64, o2080. doi.org/10.1107/S1600536808031541.

17. P. Parthiban, V. Ramkumar, M. S. Kim, K. T. Lim and Y. T. Jeong, 2,4-Bis (3-bromo phenyl)-3-azabicyclo [3.3.1] nonan-9-one, Acta Cryst., 2008, E64, o2332. doi.org/10.1107/S1600536808036660

16. P. Parthiban, V. Ramkumar, M. S. Kim, K. T. Lim and Y. T. Jeong, 2,4-Bis (2-bromo phenyl)-3-azabicyclo [3.3.1] nonan-9-one, Acta Cryst., 2008, E64, o2385. doi.org/10.1107/S1600536808037501

15. P. Parthiban, V. Ramkumar, M. S. Kim, K. T. Lim and Y. T. Jeong , 2,4-Bis(2-chloro phenyl)-3-azabicyclo [3.3.1]nonan-9-one, Acta Cryst., 2008, E64, o1586. doi.org/10.1107/S160053680802268X.

14. P. Parthiban, V. Ramkumar, N. A. Kumar, J. S. Kim and Y. T. Jeong, r-2, c-6-Bis(3­methoxyphenyl)-t-3, t-5-dimethylpiperidin-4-one, Acta Cryst., 2008, E64, o1631. doi.org/10.1107/S1600536808023490

13. P. Parthiban, K. Thirumurugan, V. Ramkumar, S. Pazhamalai and Y. T. Jeong 2,4-Bis (3­fluoro phenyl)-3-azabicyclo [3.3.1] nonan-9-one, Acta Cryst., 2008, E64, o1708-o1709. doi.org/10.1107/S1600536808024690

12. P. Parthiban, V. Ramkumar, H. D. Santan, J. T. Kim and Y. T. Jeong, 2,4-Bis (4-fluoro phenyl)-3-azabicyclo [3.3.1] nonan-9-one, Acta Cryst., 2008, E64, o1710. org/10.1107/S1600536808024744

11. G. Ramachandran, R. Suresh, S. Sreedevi, Charles C. Kanakam and V. Ramkumar, 6­Formyl-2-methoxy-3-nitrophenyl 4-toluenesulfonate, Acta Cryst., 2008, E64, o2046. doi.org/10.1107/S1600536808029711

10. P. Parthiban, S. Umamatheswari, A. Doddi, V. Ramkumar and S. Kabilan, r-2, c-6-Bis(4­bromophenyl)-t-3,t-5-dimethyltetrahydropyran-4-one, Acta Cryst., 2007, E63, o4373. doi.org/10.1107/S1600536807050660

09. R. Ramachandran, P. Parthiban, A. Doddi, V. Ramkumar and S. Kabilan, r-2, c-6-Bis(3­fluorophenyl)-t-3, t-5-dimethylpiperidin-4-one, Acta Cryst., 2007, E63, o4559. doi.org/10.1107/S1600536807054165

08. T. Augustine, V. Ramkumar and Charles C. Kanakam, 1′-Methyl-4′-phenylacenaphthene­1-spiro-2′-pyrrolidine-3′-spiro-3”-benzo [ g] chroman-2,4”-dione, Acta Cryst., 2007, E63, o4717. doi.org/10.1107/S1600536807056796

07. T. Augustine, C. C. Kanakam, R. Suresh, Y. Christurajan and V. Ramkumar, 6-Methoxy­1′-methyl-4′-phenylchroman-3-spiro-3′-pyrrolidine-2′-spiro-3”(2”H)-indole-2”,4-dione. Acta Cryst., 2007, E63, o3794. doi.org/10.1107/S1600536807038755

06. T. Augustine, V. Ramkumar, S. Arul Antony and C. C. Kanakam, 6”-Methoxy-1’­methyl-4′-phenylacenaphthene-1-spiro-2′-pyrrolidine-3′-spiro-3”-chroman-2,4”-dione, Acta Cryst., 2007, E63, o4412. doi.org/10.1107/S1600536807051264

05. A. Doddi, T. A. Luiz, V. Ramkumar and M. N. S. Rao, cis-Bis (benzyl methyl phenyl phosphine-P) tetracarbonylmolybdenum(0), Acta Cryst., 2007, E63, m2727. doi.org/10.1107/S1600536807048982

04. S. Rajeswari, G. Venkatesa Prabhu, K. Krishnakumar, V. Ramkumar and B. Varghese, 1-[(2,5-Dioxopyrrolidin-1-yl) (phenyl)methyl] urea. Acta Cryst. 2007, E63, o2929. doi.org/10.1107/S1600536807022799.

03. Quentin Hanley and V. Ramkumar, An Internal standardization procedure for Spectrally resolved Fluorescence Life Imaging Microscope (sFLIM). App. Spect., 2005, 59, 261­266. doi.org/10.1366/000370205308

02. S. Velu, V. Ramkumar, A. Narayanan and C. S. Swamy, Effect of interlayer anion on the Physicochemical properties of Zinc aluminium hydrotalcites, J. Mat. Sci., 1997, 32, 957. doi.org/10.1023/A:1018561918863

01. S. Kannan, S. Velu, V. Ramkumar and C. S. Swamy, Synthesis and physicochemical properties of cobalt aluminium hydrotalcite, J. Mat. Sci., 1995, 30, 1462-1468. doi.org/10.1007/BF00375249

BOOK CHAPTER

01.Indrajit Das, V. Ramkumar, R.L.Gardas, Thermodynamic Analysis of Ionic Liquids for CO₂ Capture, Regeneration and Conversion, Climate Change and Green Chemistry of CO₂ Sequestration, 2021, 123-140.

US Patent

01. D Chakraborty, S Ghosh, Venkatachalam Ramkumar, Catalyst for poly (lactide) synthesis and uses there of, (US Patent App. 14/781, 016 – US 2016/0053048 A1).

Indian Patents

01. Ravikumar R. Gowda, Debashis Chakraborty and Venkatachalam Ramkumar, Group 4 metal aryloxy compounds as bulk polymerization catalysts for lactide polymerization, (Indian Patent Application No:2550/CHE/2010 – Patent No: 317875).

02. Ravikumar R. Gowda, Debashis Chakraborty and Venkatachalam Ramkumar, Group 4 metal aryloxy compounds, (Indian Patent Application No:1376/CHE/2011- Patent No: 284011).

03. Debashis Chakraborty, Payal Malik, Ravikumar R. Gowda and Venkatachalam Ramkumar, Metal free catalysts for the ring-opening polymerization of cyclic esters and lactide, (Indian Patent Application No: 4571/CHE/2011 – Patent No: 319790).

04. Debashis Chakraborty, Swarup Ghosh, Venkatachalam Ramkumar, Imino(phenoxy) alane: A High Mileage Catalyst for PLA Synthesis, (Patent Application in Progress).