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Ghosh, Keya ; Ghatak, U. R. (2001) A novel route to functionalized linearly benzannulated medium ring carbocyclics through regioselective aryl radical cyclization Journal of the Indian Institute of Science, 81 (3). pp. 239-264. ISSN 0970-4140

Ghosh, Keya ; Ghatak, Usha Ranjan (1999) Synthetic studies towards complex diterpenoids. Part 20. Total synthesis of the linear abietane o-quinone umbrosone Journal of the Chemical Society, Perkin Transactions 1 (10). pp. 1359-1362. ISSN 0300-922X

Ghosh, Ajit K. ; Mukhopadhyaya, Jayanta K. ; Ghatak, Usha Ranjan (1997) Regioselective aryl radical cylization. Part 2.1 Synthesis of octahydro-1H-dibenzo[a,d]cycloheptenes through 7-endo ring closure Journal of the Chemical Society, Perkin Transactions 1 (18). pp. 2747-2756. ISSN 0300-922X

Ghosh, Keya ; Ghatak, Usha Ranjan (1995) Regioselective 9-endo aryl radical cyclisation: a new synthetic route to decahydro-5H -dibenzo[a,d] and [a,e]-cyclononenols Tetrahedron Letters, 36 (27). pp. 4897-4900. ISSN 0040-4039

Mukhopadhyaya, Jayanta K. ; Pal, Sitaram ; Ghatak, Usha Ranjan (1995) An efficient palladium catalyzed stereocontrolled synthesis of 4a-angular methyl substituted hydrofluorenes Synthetic Communications, 25 (11). pp. 1641-1657. ISSN 0039-7911

Ghosh, Keya ; Ghatak, Usha Ranjan (1994) First total synthesis of the linear abietane diterpenoid orthoquinone umbrosone Tetrahedron Letters, 35 (32). pp. 5943-5944. ISSN 0040-4039

Pal, Sitaram ; Mukhopadhyaya, Jayanta K. ; Ghatak, Usha Ranjan (1994) Regioselective aryl radical cyclization. 1. Stereocontrolled synthesis of linearly condensed hydroaromatic carbocyclic systems through 6-endo-ring closures Journal of Organic Chemistry, 59 (10). pp. 2687-2694. ISSN 0022-3263

Pal, Sitaram ; Banik, Bimal K. ; Ghatak, Usha Ranjan (1994) Condensed cyclic and bridged-ring systems. Part 15. Acid-catalyzed intramolecular alkylations in 1-diazoacetyl-1,2,3,4-tetrahydro-9- methoxy-1-methylphenanthrenes Journal of the Chemical Society, Perkin Transactions 1 (8). pp. 1105-1110. ISSN 0300-922X

Ghosh, Keya ; Ghosh, Ajit K. ; Ghatak, Usha Ranjan (1994) Highly regioselective 8-endo-aryl radical cyclisation: a new synthetic route to decahydrodibenzo-[a,d]- and -[a,e]-cyclooctenols Journal of the Chemical Society, Chemical Communications (5). pp. 629-630. ISSN 0022-4936

Ghosh, Ajit K. ; Mukhopadhyay, Chhanda ; Ghatak, Usha Ranjan (1994) Synthetic studies towards complex diterpenoids. Part 19. Total synthesis of (±)-deoxofaveline, (±)-faveline methyl ether and ( ±)-faveline Journal of the Chemical Society, Perkin Transactions 1 . pp. 327-332. ISSN 0300-922X

Deb, S. ; Chakraborti, R. ; Ghatak, U. R. (1993) Synthesis of 1-p-methoxyphenyl- and 1-(p-methoxyphenyl)-4- methylbicyclo(2.2.1)heptan-7-one. The oxidation of 7-hydroxy-1-(p- methoxyphenyl)-4-methylbicyclo(2.2.1)heptane-7-carboxylic acid with lead tetraacetate Synthetic Communications, 23 (7). pp. 913-924. ISSN 0039-7911

Ghosh, Ajit K. ; Ghosh, Keya ; Pal, Sitaram ; Ghatak, Usha Ranjan (1993) Highly regioselective 7-endo-aryl radical cyclisation: synthesis of octahydro-2H-dibenzo[a,d]cycloheptenes Journal of the Chemical Society, Chemical Communications (9). pp. 809-811. ISSN 0022-4936

Pal, Sitaram ; Mukherjee, Monika ; Mukherjee, Alok K. ; Helliwell, M. ; Ghatak, Usha Ranjan (1992) The correct structures of the ortho-cyclized products in the cycloalkylations of 1-m-methoxybenzyl-4,4a,5,6,7,8-hexahydronaphthalen-2(3H)-one and 1-m-methoxybenzyl-octalins: X-ray structure determination of (±)-4-methoxy-9a-carbamorphinan-16-one Synthetic Communications, 22 (17). pp. 2509-2512. ISSN 0039-7911

Ghosh, Sukumar ; Ghosh, Ajit K. ; Ghatak, Usha Ranjan (1992) An expeditious stereoselective total synthesis of (±)-podocarpa-2,8,11.13-tetraene and 3-oxygenated (±)-podocarpa-8,11,13-trienes by acid-catalyzed cyclialkylation route Synthetic Communications, 22 (4). pp. 553-565. ISSN 0039-7911

Ghosh, Ajit K. ; Ray, Chhanda ; Ghatak, Usha Ranjan (1992) First total synthesis of the novel cytotoxic benzocycloheptenes (±)-deoxofaveline and (±)-faveline methyl ether Tetrahedron Letters, 33 (5). pp. 655-658. ISSN 0040-4039

Ghosh, Sukumar ; Ghatak, Usha Ranjan (1992) Influence of electron donating aromatic substituents on the ruthenium tetroxide-catalysed oxidation of (±)-podocarpa-8,11,13-trienes Tetrahedron, 48 (35). pp. 7289-7296. ISSN 0040-4020

Pal, Sitaram ; Banik, Bimal K. ; Ghatak, Usha Ranjan (1992) A facile synthetic route to 1,1-disubstituted 2,3-dihydro-1H-benz[f]indene-4,9-diones Synthesis (11). pp. 1073-1075. ISSN 0039-7881

Ray, Chhanda ; Saha, Bijali ; Ghatak, Usha Ranjan (1991) Synthesis of some angularly cyclopentanone fused hydrophenanthrene and hydrofluorene derivatives by acid-catalyzed intramolecular C-alkylation of γ,δ - unsaturated α'-diazomethyl ketones Synthetic Communications, 21 (10-11). pp. 1223-1242. ISSN 0039-7911

Ghosh, Sukumar ; Banik, Bimal K. ; Ghatak, Usha Ranjan (1991) Influence of electron donating aromatic substituents on the stereochemistry of the products in cycloalkylations of 2-(2-arylethyl)-3,3-dimethyl-1-methylenecyclohexane and related substrates: mechanisms of aromatic cycloalkylations Journal of the Chemical Society, Perkin Transactions 1 (12). pp. 3189-3193. ISSN 0300-922X

Ghosh, Sukumar ; Banik, Bimal K. ; Ghatak, Usha Ranjan (1991) An expeditious synthesis of 1,2,3,4-tetrahydro-1,1- dimethylphenanthrenes Journal of the Chemical Society, Perkin Transactions 1 (12). pp. 3195-3197. ISSN 0300-922X

Pal, Sitaram ; Mukherjee, Monika ; Podder, Debi ; Mukherjee, Alok K. ; Ghatak, Usha Ranjan (1991) A highly regioselective 6-endo-aryl radical cyclisation: stereocontrolled synthesis of trans-octahydroanthracenes Journal of the Chemical Society , Chemical Communications (22). pp. 1591-1593. ISSN 0022-4936

Pal, Sitaram ; Ghosh, Sukumar ; Banik, Bimal K. ; Alam, Shaikh Khairul ; Ghatak, Usha Ranjan (1990) Synthesis of (±)-2-methoxy-9a-carbamorphinan and (±)-2-methoxy-9a-carba-14α-morphinan: acid catalyzed cyclizations of 1-m̲-methoxybenzyl-4, 4a,5,6,7,8-hexahydronaphthalen-2(3H)-one and 1-m̲-methoxy benzyloctalins Synthetic Communications, 20 (14). pp. 2203-2216. ISSN 0039-7911

Ray, Chhanda ; Saha, Bijali ; Ghatak, Usha Ranjan (1990) Condensed cyclic and bridged-ring systems-14. Synthesis of some bridged propano-hydrophenanthrene, -hydrofluorene and polycyclic benzo-propellane derivatives through intramolecular c-alkylations of γ δ-unsaturated α'-diazomethyl ketones Tetrahedron, 46 (8). pp. 2857-2870. ISSN 0040-4020

Deb, Soumitra ; Bhattacharjee, Gopa ; Ghatak, Usha Ranjan (1990) Synthetic studies towards complex diterpenoids. Part 18. Total synthesis of (±)-isopisiferin and the related compounds Journal of the Chemical Society, Perkin Transactions 1 (5). pp. 1453-1458. ISSN 0300-922X

Ghatak, U. R. (1990) An expeditious total synthetic route to naturally occurring tricarbocycIic ring ring-C-aromatic diter penoids: mechanisms of cyclialkylations Pure and Applied Chemistry, 62 (7). pp. 1413-1416. ISSN 0033-4545

Banik, Bimal K. ; Ghatak, Usha Ranjan (1989) Synthetic studies towards complex diterpenoids-171: synthesis and oxidative cleavage of (±)-19,20-cycloabieta-19-oxo-8,11,13-triene Tetrahedron, 45 (11). pp. 3547-3556. ISSN 0040-4020

Ghosh, Subrata ; Ghatak, Usha Ranjan (1988) Carbon-carbon bond formation and annulation reactions using trimethyl and triethyl orthoformates Proceedings of the Indian Academy of Sciences - Chemical Sciences, 100 (2-3). pp. 235-252. ISSN 0253-4134

Banik, Bimal K. ; Ghosh, Sukumar ; Ghatak, Usha Ranjan (1988) Influence of methoxy-and methyl-aromatic substituents on stereochemistry of the products in the acid-catalyzed cyclization of 2-(2-arylethyl)-1,3,3-trimethylcyclohexanols: stereocontrolled total synthesis of (±)-nimbidiol and (±)-nimbiol Tetrahedron, 44 (22). pp. 6947-6955. ISSN 0040-4020

Saha, Bijali ; Bhattacharjee, Gopa ; Ghatak, Usha Ranjan (1988) Vinylogous Wolff rearrangement of cyclic β,γ-unsaturated diazomethyl ketones: a new synthetic method for angularly functionalised polycyclic systems Journal of the Chemical Society, Perkin Transactions 1 (4). pp. 939-944. ISSN 0300-922X

Ranu, Brindaban C. ; Chakraborti, Ratna ; Ghatak, Usha Ranjan (1988) A formylation-cyclisation method of synthesis of cycloalkenones from unsaturated ketones. Part 3. Simple synthesis of some functionalised angularly fused cyclopentenone and cyclopentanone derivatives Journal of the Chemical Society, Perkin Transactions 1 (4). pp. 795-801. ISSN 0300-922X

Chakraborti, Ratna ; Ranu, Brindaban C. ; Ghatak, Usha Ranjan (1987) Stereospecific synthesis of endo-6-aryl-2-oxobicyclo [3.3.1]nonanes Synthetic Communications, 17 (13). pp. 1539-1543. ISSN 0039-7911

Saha, Bijali ; Satyanarayana, Gutta O. S. V. ; Ghatak, Usha Ranjan (1987) Acid-catalysed intramolecular C-alkylation in β,γ-unsaturated diazomethyl ketones. Part 5. Synthesis of functionalised hydrofluorene derivatives via novel fragmentation reactions Journal of the Chemical Society, Perkin Transactions 1 . pp. 1263-1268. ISSN 0300-922X

Chkraborty, Asit K. ; Saha, Bijali ; Ray, Chhanda ; Ghatak, Usha Ranjan (1987) Alkali metal-liquid ammonia reduction of γ-lactones to diols and cyclic hemiacetals: stereochemical influence by the neighbouring group on the nature Tetrahedron, 43 (19). pp. 4433-4437. ISSN 0040-4020

Chakraborti, Asit K. ; Alam, Shaikh Khairul ; Chakraborti, Prabir C. ; Dasgupta, Rupak ; Chakravarty, Jyotirmoy ; Ghatak, Usha Ranjan ; Kabiraj, Apurba ; Biswas, Sundar Gopal (1986) Condensed cyclic and bridged-ring systems. Part 13. Synthesis of the insect attractant hydrocarbon, 9a-carbamorphinan, and X-ray structural analyses of 9a-carbamorphinan-10-one and 9a-carba-14α-morphinan-10-one Journal of the Chemical Society, Perkin Transactions 1 . pp. 1243-1248. ISSN 0300-922X

Saha, Bijali ; Bhattacharjee, Gopa ; Ghatak, Usha Ranjan (1986) A novel synthetic method for angularly functionalized polycyclic systems by vinylogous wolff rearrangement of β,γ-unsaturated diazoketones Tetrahedron Letters, 27 (33). pp. 3913-3914. ISSN 0040-4039

Chakraborti, Ratna ; Ranu, Brindaban C. ; Ghatak, Usha Ranjan (1985) A formylation-cyclization method of synthesis of cycloalkenones from unsaturated ketones. 2. Simple synthesis of some functionalized bicyclo[3.3.1]nonane derivatives Journal of organic Chemistry, 50 (25). pp. 5268-5271. ISSN 0022-3263

Kanjilal, Pranab R. ; Sarkar, Manish ; Patra, Swapan K. ; Ghosh, Subrata ; Ghatak, Usha Ranjan (1985) Synthetic studies toward complex diterpenoids. 16. a novel synthetic route to the carbocyclic skeleta of stemodin and stemarin by acid-catalyzed intramolecular C-alkylation and rearrangement reactions Journal of Organic Chemistry, 50 (6). pp. 857-863. ISSN 0022-3263

Saha, Bijali ; Roy, Subhas C. ; Satyanarayana, Gutta O. S. V. ; Ghatak, Usha Ranjan ; Seal, Alpana ; Ray, Siddhartha ; Bandyopadhyay, Ramrenu ; Ghosh, Minakshi ; Das, Birendranath ; Basak, Bijoy S. (1985) Acid-catalysed intramolecular C-alkylation in β,γ-unsaturated diazomethyl ketones. Part 4. Synthesis of functionalised hydrophenanthrene and benzocyclodecenone derivatives via novel fragmentation reactions, and X-ray structural analyses of two angularly substituted hydrophenanthrene derivatives Journal of the Chemical Society, Perkin Transactions 1 . pp. 505-513. ISSN 0300-922X

Dasgupta, Ratna ; Kanjilal, Pranab R. ; Patra, Swapan K. ; Sarkar, Manish ; Ghatak, Usha Ranjan (1985) Condensed cyclic and bridged-ring systems : part 12: a novel synthetic route to 4-p-methoxyphenyl-bicyclo[ 2.2.2 ]octan-2-ones and some bicyclo [ 3.2.1 ] octane derivatives by acid-catalyzed intramolecula Tetrahedron, 41 (23). pp. 5619-5625. ISSN 0040-4020

Chakraborti, Asit K. ; Ghatak, Usha Ranjan (1985) A highly effective ligand-bound ruthenium catalyst for chemoselective degradation of aromatic rings to carboxylic acids Journal of the Chemical Society, Perkin Transactions 1 (12). pp. 2605-2609. ISSN 0300-922X

Dasgupta, Ratna ; Ghatak, Usha Ranjan (1985) A simple synthesis of α, β-unsaturated aldehydes by 1,3-carbonyl transposition through one carbon homologation Tetrahedron Letters, 26 (12). pp. 1581-1584. ISSN 0040-4039

Ghosh, Subrata ; Ghatak, Usha Ranjan (1984) A facile synthetic route to complex polycyclic natural products through intramolecular alkylation with α-diazomethyl ketones Proceedings of the Indian Academy of Sciences - Chemical Sciences, 93 (4). pp. 547-563. ISSN 0253-4134

Bhattacharjee, Gopa ; Ghatak, Usha Ranjan ; Chakravarty, Ajit K. (1984) Condensed cyclic and bridged-ring systems. Part 10. Alumina-induced regioselective intramolecular alkylations of cis- and trans-4a-(2-methylsulphonyloxyethyl)-3,4,4a,9,10,10a-hexahydrophenanthren-2(1H)-ones Journal of the Chemical Society, Perkin Transactions 1 . pp. 1515-1523. ISSN 0300-922X

Chakraborti, Asit K. ; Ray, Jayanta K. ; Kundu, Kalyan K. ; Chakrabarty, Sephali ; Mukherjee, Debabrata ; Ghatak, Usha Ranjan (1984) Regioselectivity in the intramolecular carbon-hydrogen insertion in metal-catalysed decomposition of some cis-1-methyl-3-arylcyclohexyl diazomethyl ketones. A highly efficient homogeneous nickel catalyst for carbenoid insertion Journal of the Chemical Society, Perkin Transactions 1 (2). pp. 261-273. ISSN 0300-922X

Sinha, Gopa ; Maji, Santosh K. ; Ghatak, Usha Ranjan ; Mukherjee, Monika ; Mukherjee, Alok K. ; Chakravarty, Ajit K. (1983) Condensed cyclic and bridged-ring system. Part 9. Stereocontrolled synthesis and X-ray structural analyses of cis-3,4,4a,9,10,10a-hexahydro-1,4a-ethanophenanthrene-2(1H),12-dione and trans-3,4,4a,9,10,10a-hexahydro-3,4a-ethanophenanthrene-2(1H), 12-dione Journal of the Chemical Society, Perkins Transactions1 (10). pp. 2519-2528. ISSN 0300-922X

Chakraborti, Asit K. ; Ghatak, Usha Ranjan (1983) Extension of an improved procedure for the ruthenium tetroxide-catalyzed degradation of aromatic rings: a highly efficient and stereocontrolled synthesis of functionalized bridged-ring and carbocyclic esters Synthesis (9). pp. 746-748. ISSN 0039-7881

Roy, Subhas C. ; Satyanarayana, Gutta O. S. V. ; Ghatak, Usha Ranjan (1982) Acid-catalyzed intramolecular C-alkylation in β,γ-unsaturated diazomethyl ketones. 3. A simple synthetic route to hexahydro-4,9a-ethano-1H-fluoren-11-ones, hexahydro-6H·pentaleno[6a,1-a]indan-4-ones and hexahydrocyclobuta[j]fluoren-2(1H)-ones Journal of Organic Chemistry, 47 (27). pp. 5361-5368. ISSN 0022-3263

Satyanarayana, Gutta O. S. V. ; Roy, Subhas C. ; Ghatak, Usha Ranjan (1982) Acid-catalyzed intramolecular C-alkylation in β,γ-unsaturated diazomethyl ketones. 2. A simple new synthetic route to octahydro-4,10a-ethanophenanthren-12-ones and octahydropentaleno[6a,1-a]naphthalen-4-ones Journal of Organic Chemistry, 47 (27). pp. 5353-5361. ISSN 0022-3263

Ranu, Brindaban C. ; Sarkar, Manish ; Chakraborti, Prabir C. ; Ghatak, Usha Ranjan (1982) Synthetic studies directed towards complex diterpenoids. Part 15. Synthesis and stereochemistry of the catalytic reduction of Δ4b(5)-gibbenes and related compounds Journal of the Chemical Society, Perkin Transactions 1 . pp. 865-873. ISSN 0300-922X

Ghatak, U. R. (1981) Acid-catalysed intra-molecular C-alkylation and alkylation-rearrangements through unsaturated diazomethyl ketones. A new varsatile approach to the synthesis of complex carbocylic systems Current Science, 50 (21). pp. 927-932. ISSN 0011-3891

Ghosh, Subrata ; Ghatak, Usha Ranjan (1981) Novel synthetic route to angularly functionalized hydrofluorene derivatives by a regio- and stereospecific metalation-carbonation reaction Journal of Organic Chemistry, 46 (7). pp. 1486-1490. ISSN 0022-3263

Ghatak, Usha Ranjan ; Sanyal, Baijayanti ; Satyanarayana, Gutta O. S. V. ; Ghosh, Subrata (1981) Acid-catalysed intramolecular C-alkylation in βγ-unsaturated diazomethyl ketones. A new synthetic route to angularly fused cyclobutanones, bridged cyclopentanones, and γ-lactones Journal of the Chemical Society, Perkin Transactions 1 . pp. 1203-1212. ISSN 0300-922X

Satyanarayana, Gutta O. S. V. ; Kanjilal, Pranab R. ; Ghatak, Usha R. (1981) Acid-catalysed intramolecular C-alkylation rearrangements of βγ-unsaturated diazomethyl ketones. A noval synthetic entry to pentaleno-annelated polycyclic systems Journal of the Chemical Society, Chemical Communications (15). pp. 746-747. ISSN 0022-4936

Kanjilal, Pranab R. ; Alam, Shaikh Khairul ; Ghatak, Usha R. (1981) An improved total synthesis of (±) - podocarpic acid by a cyclialkylation route Synthetic Communications, 11 (10). 795- 802. ISSN 0039-7911

Ghatak, Usha R. ; Sanyal, Baijayanti ; Ghosh, Subrata ; Sarkar, Manish ; Raju, Muppala S. ; Wenkert, Ernest (1980) A formylation-cyclization method of synthesis of cycloalkenones from unsaturated ketones Journal of Organic Chemistry, 45 (6). pp. 1081-1085. ISSN 0022-3263

Ghosh, Subrata ; Dasgupta, Rupak ; Chakravarty, Jyotirmoy ; Ghatak, Usha Ranjan (1980) Synthetic studies towards complex diterpenoids. Part 11. stereochemically defined synthesis of the racemates of 1,2,3,4,4a,9a-hexahydro-7-methoxy-1-methylfluorene-1-carboxylic acid Journal of the Chemical Society, Perkin Transactions 1, 1 . pp. 804-808. ISSN 0300-922X

Ghatak, Usha Ranjan ; Ghosh, Subrata ; Sanyal, Baijayanti (1980) Synthetic studies towards complex diterpenoids. Part 13. Stereo-specific synthesis of intermediates to the diterpene alkaloids and the C20-gibberellins by a novel rearrangement of angularly fused cyclo-butanones Journal of the Chemical Society, Perkin Transactions 1, 1 . pp. 2881-2886. ISSN 0300-922X

Ghatak, Usha Ranjan ; Chakraborti, Prabir C. (1979) Synthetic studies toward complex diterpenoids. Stereocontrolled total synthesis of some gibbane synthons and degradation products of gibberellins Journal of Organic Chemistry, 44 (25). pp. 4562-4566. ISSN 0022-3263

Ghatak, Usha Ranjan ; Chatterjee, Nithar Ranjan ; Sanyal, Baijayanti (1979) Condensed cyclic and bridged-ring systems. 8. Factors influencing the stereochemistry of the products in the acid-catalyzed cycloalkylation reactions of some substituted β-phenylethylcyclohexene and -cyclohexanol derivatives Journal of Organic Chemistry, 44 (12). pp. 1992-1999. ISSN 0022-3263

Meer, Robert K. Vander ; Ghatak, Usha R. ; Alam, Shaikh Khairul ; Chakraborti, Prabir C. (1979) (±)-des-N-morphinan: a unique bridged hydrocarbon attractant for the rhinoceros beetle, Oryctes rhinoceros; and development of an olfactometer Environmental Entomology, 8 (1). pp. 6-10. ISSN 0046-225X

Ghatak, Usha Ranjan ; Alam, Shaikh Khairul ; Ray, Jayanta K. (1978) Synthetic studies toward complex diterpenoids. 10. Stereocontrolled total synthesis of (.+-.)-19α,20α-(acetylimino)-12-hydroxy-5β,10α-podocarpa-8,11,13-triene, a degradation product of atisine Journal of Organic Chemistry, 43 (24). pp. 4598-4604. ISSN 0022-3263

Ghatak, U. R. ; Sarkar, Manish ; Patra, Swapan K. (1978) Angular alkylation through a novel intramolecular cationic cyclization reaction. A simple stereospecific route to polycyclic bridged-ring intermediates towards some complex diterpenoids Tetrahedron Letters, 19 (32). pp. 2929-2932. ISSN 0040-4039

Ghatak, Usha R. ; Ray, Jayanta K. (1977) Condensed cyclic and bridged-ring systems. Part 6. Stereochemically defined synthesis of (±)-3-methoxy-17,18,19,20-tetranor-B-homophylloclada-1(10),2,4-triene-16-one through intramolecular alkylation of a γδ-unsaturated α'-diazomethyl ketone Journal of the Chemical Society, Perkin Transactions 1 (5). pp. 518-520. ISSN 0300-922X

Ghatak, Usha R. ; Sanyal, Baijayanti ; Ghosh, Subrata (1976) A novel rearrangement of angularly fused cyclobutanone. Stereospecific syntheses of intermediates to the diterpene alkaloids and the C20 gibberellins Journal of the American Chemical Society, 98 (12). pp. 3721-3722. ISSN 0002-7863

Ghatak, Usha R. ; Chakrabarty, Sephali (1976) Synthetic studies toward complex diterpenoids. IX. New stereocontrolled synthetic route to some intermediates for diterpenoid alkaloids and C20 gibberellins Journal of Organic Chemistry, 41 (7). pp. 1089-1094. ISSN 0022-3263

Ghatak, Usha R. ; Alam, Shaikh Khairul ; Chakraborti, Prabir C. ; Ranu, Brindaban C. (1976) Condensed cyclic and bridged-ring systems. Part IV. Stereochemically controlled synthesis of some endo-2-aryl-6-oxobicyclo[3.2.1]octanes and related compounds through intramolecular alkylations of γδ-unsaturated α'-diazomethyl ketones Journal of the Chemical Society, Perkin Transactions 1 (16). pp. 1669-1673. ISSN 0300-922X

Ghatak, Usha R. ; Ray, Jayanta K. ; Chakrabarty, Sephali (1976) Condensed cyclic and bridged-ring systems. Part V. Application of the interamolecular oxo-carbenoid insertion reaction to the preparation of two new bridged-ring ketones Journal of the Chemical Society, Perkin Transactions 1 (18). pp. 1975-1976. ISSN 0300-922X

Ghatak, Usha R. ; Chakravarty, Jyotirmoy ; Dasgupta, Rupak ; Chakraborti, Prabir C. (1975) Condensed cyclic and bridged-ring systems. Part III. Regioselectivity and stereoselectivity in the acid-catalysed cyclisations of substituted benzylcyclohexanols. Stereocontrolled synthesis of some gem-carboxy-methyl-substituted hexahydrofluorene and hexahydro-5,9-methanobenzocyclo-octene derivatives Journal of the Chemical Society, Perkin Transactions 1 (23). pp. 2438-2445. ISSN 0300-922X

Chakrabarty, Sephali ; Ray, Jayanta K. ; Mukherjee, Debabrata ; Ghatak, Usha R. (1975) Regioselective intramolecular carbon-hydrogen insertion in copper-catalyzed carbenoid decompositions of cis-1-methyl-3-arylcyclohexane-1-diazomethyl ketones : some synthetic applications Synthetic Communications, 5 (4). pp. 275-281. ISSN 0039-7911

Ghatak, Usha R. ; Sanyal, Baihayanti (1974) Intramolecular C-alkylation in β,γ-unsaturated diazo ketones: a new synthetic route to angularly fused cyclobutanones and γ-lactones Journal of the Chemical Society, Chemical Communications (21). pp. 876-877. ISSN 0022-4936

Ghatak, U. R. ; Dasgupta, R. ; Chakravarty, J. (1974) Synthetic studies towards complex diterpenoids-VII : stereoselective synthesis and conformational analysis of all four possible racemates of 1,2,3,4,4a,9a-hexadydro-1-methylfluorene-1-carboxylic acids Tetrahedron, 30 (1). pp. 187-194. ISSN 0040-4020

Ghatak, Usha R. ; Chakrabarty, Sephali ; Rudra, Kalpana (1974) Synthetic studies towards complex diterpenoids. Part VIII. Stereo-controlled synthesis of (±)-2-methoxy-11β-methyl-4bαH-gibba-1(10a),2,4-trien-8-one and related compounds through intramolecular alkylations of γδ-unsaturated α'-diazomethyl ketones Journal of the Chemical Society, Perkin Transactions 1 . pp. 1957-1961. ISSN 0300-922X

Ghatak, Usha R. ; Charkraborti, Prabir C. ; Ranu, Brindaban C. ; Sanyal, Baijayanti (1973) Intramolecular keto-carbenoid addition to double bonds: stereochemistry of the catalytic reduction of Δ9(11)-gibbenes and related compounds Journal of the Chemical Society, Chemical Communications (15). pp. 548-549. ISSN 0022-4936

Ghatak, U. R. ; Chakrabarty, Sephali (1972) Angular alkylation through intramolecular carbenoid insertion. New stereocontrolled route to synthetic intermediates to the diterpene alkaloids and C20 -gibberellins Journal of American Chemical Society, 94 (13). pp. 4756-4758. ISSN 0002-7863

Kovacs, J. ; Kapoor, A. ; Ghatak, U. R. ; Mayers, G. L. ; Giannasio, V. R. ; Giannotti, R. ; Senyk, George ; Nitecki, Danute E. ; Goodman, Joel W. (1972) Synthesis of poly-γ-glutamyl-γ-aminobutyric acids and their reactivity with antiserum against Bacillus anthracis polypeptide Biochemistry, 11 (10). pp. 1953-1958. ISSN 0006-2960

Kovacs, J. ; Kalita, C. ; Ghatak, U. R. (1972) Synthesis of polyglutathione, polyasparthione, and related sequential polypeptides Journal of Organic Chemistry, 37 (1). pp. 30-34. ISSN 0022-3263

Chakrabortty, P. N. ; Dasgupta, R. ; Dasgupta, S. K. ; Ghosh, S. R. ; Ghatak, U. R. (1972) Synthetic studies towards complex diterpenoids-VI : new synthetic routes to tetracyclic bridged-bicyclo[3.2.1]octane intermediates by intramolecular alkylation reactions through α-diazomethyl ketones of hydroaromatic γ,δ-unsaturated acids Tetrahedron, 28 (17). pp. 4653-4665. ISSN 0040-4020

Johnson, L. F. ; Chakravarty, J. ; Dasgupta, R. ; Ghatak, U. R. (1971) Application in the use of a shift reagent in proton magnetic resonance spectroscopy for the elucidation of structures and stereochemistry of epimeric methyl 4,9-dimethyl-7, 8-benzobicyclo (3.3.1)non-7-ene-4-carboxylates Tetrahedron Letters, 12 (20). pp. 1703-1708. ISSN 0040-4039

Ghatak, Usha Ranjan ; Chatterjee, Nithar Ranjan (1971) A total synthesis of (±)-O-methyl-14-methylpodocarpic acid Journal of the Chemical Society C: Organic . pp. 190-196. ISSN 0022-4952

Kovacs, Joseph ; Mayers, George L. ; Johnson, Robert Hall ; Cover, Richard E. ; Ghatak, Usha R. (1970) Racemization of amino acid derivatives. III. Rate of racemization and peptide bond formation of cysteine active esters Journal of Organic Chemistry, 35 (6). pp. 1810-1815. ISSN 0022-3263

Moore, R. E. ; Ghatak, U. R. ; Chakravarty, J. ; Dasgupta, R. ; Johnson, L. F. (1970) Mass spectrometry and proton and carbon-13 nuclear magnetic resonance spectroscopy in assigning stereochemistry to derivatives of des-N-morphinan and des-N-isomorphinan Journal of the Chemical Society D: Chemical Communications (18). pp. 1136-1138. ISSN 0577-6171

Kovacs, J. ; Mayers, G. L. ; Johnson, R. H. ; Cover, R. E. ; Ghatak, U. R. (1970) Rates of racemization and coupling of cysteine active ester derivatives Journal of the Chemical Society D: Chemical Communications (1). pp. 53-54. ISSN 0022-4936

Ghatak, U. R. ; Chatterjee, N. R. ; Banerjee, A. K. ; Chakravarty, J. ; Moore, Richard E. (1969) Synthesis and conformational analysis of tricyclic ring-C aromatic 20-nor diterpenoid resin acid analogs Journal Of Organic Chemistry, 34 (12). pp. 3739-3749. ISSN 0022-3263

Kovacs, J. ; Schmit, G. N. ; Ghatak, U. R. (1968) Polypeptides with known repeating sequences of amino acids. Comparison of several methods used for the synthesis of poly-γ-D- and L-glutamylglycine and investigation of its serological reaction with antianthrax immune serum Biopolymers, 6 (6). pp. 817-836. ISSN 0006-3525

Ghatak, U. R. ; Chakravarty, J. ; Banerjee, A. K. (1968) Synthetic studies directed to gibberellins and related compounds Tetrahedron, 24 (4). pp. 1577-1593. ISSN 0040-4020

Ghatak, U. R. ; Chakravarty, J. ; Banerjee, A. K. ; Chatterjee, N. R. (1967) Proximity effects. The stereochemistry of the lithium-ammonia reduction of cyclic styrenoid systems containing a neighbouring carboxylic acid group Chemical Communications (London) (5). pp. 217-218. ISSN 0009-241X

Ghatak, U. R. ; Banerjee, A. K. ; Chatterjee, N. R. ; Chakravarty, J. (1967) Syntheses and stereochemistry of (±)-4α-methyl-10β-hydroxy-trans-1,2,3,4,5,6,7,10-octahydrophenanthrene-4β-carboxylic acid lactone and the four epimers of (±)-4-methyl-1,2,3,4,5,6,7,10-octahydro-phenanthrene-4-carboxylic acid Tetrahedron Letters, 8 (3). pp. 247-253. ISSN 0040-4039

Ghatak, U. R. ; Chatterjee, N. R. (1967) A total synthesis of (±)-sempervirol acetate Tetrahedron Letters, 8 (48). pp. 4783-4784. ISSN 0040-4039

Kovacs, J. ; Ghatak, U. R. (1966) Investigation on the sodium-liquid ammonia cleavage of a tosyl protecting group of tosylamino acids and peptides Journal of Organic Chemistry, 31 (1). pp. 119-121. ISSN 0022-3263

Ghatak, U. R. ; Chakravarty, J. (1966) Acid-catalized cylisation of substituted benzylcyclohexanols. Factors influencing the nature of cyclisation products Tetrahedron Letters, 7 (22). pp. 2449-2458. ISSN 0040-4039

Ghatak, U. R. ; Chakravarty, J. (1966) Intramolecular participation by a neighbouring ketone group in ester hydrolysis Chemical Communications (London) (7). pp. 184-185. ISSN 0009-241X

Basu, N. K. ; Ghatak, U. R. ; Sengupta, G. ; Dutta, P. C. (1965) Synthesis studies on resin acids-VII: synthesis of two isomers of 4,10-dimethyldecalin-4-carboxylic acids Tetrahedron, 21 (9). pp. 2641-2652. ISSN 0040-4020

Pettit, George R. ; Das Gupta, Arun K. ; Ghatak, Usha R. (1963) Steroids and related natural products. XVI synthesis of oxaestranes Steroids, 1 (2). pp. 137-143. ISSN 0039-128X

Sharma, M. ; Ranjan Ghatak, U. ; Chandra Dutta, P. (1963) Synthetic studies on resin acids-V: synthesis of three isomers of dehydroabietic acid Tetrahedron, 19 (6). pp. 985-994. ISSN 0040-4020

Pettit, G. R. ; Green, B. ; Kasturi, T. R. ; Ghatak, U. R. (1962) Steroids and related natural products-X: reduction of lactones Tetrahedron, 18 (8). pp. 953-958. ISSN 0040-4020

Pettit, George ; Ghatak, Usha ; Green, Brian ; Kasturi, T. ; Piatak, David (1961) Steroids and related natural products. IV. Reduction of lactones to cyclic ethers Journal of Organic Chemistry, 26 (5). pp. 1685-1686. ISSN 0022-3263

Ghatak, Usha Ranjan ; Datta, Dilip Kumar ; Ray, Suvas Chandra (1960) Synthetic studies on resin acids. IV Journal of American Chemical Society, 82 (7). pp. 1728-1734. ISSN 0002-7863

Sen, Kalyanmay ; Ghatak, Usha Ranjan (1959) Synthesis of condensed cyclic systems. I. New synthesis of 7-methylbicyclo-[3.3.0]octan-3-one and 8-methylbicyclo[4.3.0]nonan-4-one Journal of Organic Chemistry, 24 (12). pp. 1866-1869. ISSN 0022-3263

Ghatak, Usha Ranjan (1959) Stereochemistry of desoxypodocarpic acid isomers Tetrahedron Letters, 1 (1). pp. 19-23. ISSN 0040-4039

Ghatak, Usharanjan ; Saha, Narendra Nath ; Dutta, Phanindra Chandra (1957) Synthetic studies in resin acids. II Journal of the American Chemical Society, 79 (16). pp. 4487-4491. ISSN 0002-7863

This list was generated on Wed Nov 14 21:32:49 2018 UTC.