Number of items: 100.
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
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