Indian Journal of Chemistry

Sect. B: Organic Chemistry including Medicinal Chemistry

VOL. 41B

NUMBER 9

SEPTEMBER 2002

CONTENTS

 

 

Papers

 

 

1887

Facile synthesis of [1]benzopyrano[4,3-c]pyra-zoles, 1-aryl-3-(2-formamidophenyl) pyrazoles and 1-aryl-3-phenyl-4-alkylpyrazoles using Vilsmeier reagent

A facile synthesis of benzopyrano[4,3-c]pyrazoles, 1-aryl-3-(2-formamidophenyl)pyrazole and 1-aryl-3-phenyl-4-alkylpyrazoles using Vilsmeier cyclization has been reported.

 

 

 

 

 

 

S Selvi & P T Perumal*

 

 

 

 

 

 

 

 

 

 

1894

Hypervalent iodine mediated synthesis of 1,2,4-triazolo [4,3-a][1,8]naphthyridines

The title compounds 6 have been synthesized from 2-hydrazino-3-(p-chlorophenyl)-1,8-naphthyridine 4 by reaction with aromatic aldehydes followed by dehydrogenative cyclization with iodobenzene diacetate.

 

 

 

 

 

 

K Mogilaiah* & D Srinivasa Chowdary

 

 

 

 

 

 

 

 

 

1899

Amano PS catalysed methanolysis of maleimides: An efficient synthesis of methyl maleanilates

A first simple method for amano PS catalysed methanolysis of maleimides 1a-f has been described to obtain methyl maleanilates 2a-f in 80-90% yields.

 

 

Srinivasan Easwar & Narshinha P Argade*

 

 

 

 

1902

Studies on b-enaminonitriles : Part IV Reaction of b-enaminonitriles with acid chlorides

Studies on acylation of b-aminocrotononitrile with saturated acid chlorides in the presence of an added organic base are reported.

 

Kumar K Mahalanabis*, Mili Sarkar,
S K Dutta Chowdhury & C R Ghosal

 

 

 

 

 

 

 

1907

Oxidation of threose-series pentose and hexoses by N-arylbromosulphonamides in alkaline medium

N-Arylbromosulfonamides oxidizes threose-series pentoses and hexoses to a mixture of glyceric, threonic, eryhronic, xylonic, lyxonic and hexonic acids in various proportions and obey the rate law, rate = k[S][HO-] [OX]. A probable mechanism is proposed.

 

V Shashikala & K S Rangappa*

 

 

 

 

 

 

 

1915

Chemical transformation of andrographolide

The reaction of 1 with in situ generated nickel boride yields compounds 6 and 8. Monotosylation of 6 followed by reaction with NaI refluxing in acetone furnishes the iodide 13. All attempts to generate an oxetane moiety in 13 corresponding to compound 2 failed.

 

Mahesh Pal*, Meenakshi Singh & R P Sharma

 

 

 

 

 

 

 

 

1919

Structure - function correlation in lipase catalysed esterification reactions of short and medium carbon chain length alcohols and acids

An attempt has been made to correlate the chain lengths of acids and alcohols to the extent of esterification in the Rhizomucor miehei lipase catalyzed esterification reactions involving acids of carbon chain length C2 C5 and alcohols of carbon chain length C1 C8.

 

Soundar Divakar

 

 

 

 

 

 

 

1923

Towards non-vertical radical cations: Quantum chemical studies on pentafulvene and triafulvene radical cations

Fulvene radical cations are examined by semiempirical AM1 method and by ab initio calculations at HF/6-31G*, MP2/6-31G* and B3LYP/6-31G* levels. The perpendicular form of fulvene radical cations is predicted to be higher in energy than the planar form.

Triafulvene radical cation

 

 

Pentafulvene radical cation

 

 

Rebecca Jacob*, S Viswanathan &
E J Padma Malar

 

 

 

 

 

 

 

1929

Structures of some Hoechst analogues in gas phase and in aqueous solution

Conformational preferences of four Hoechst analogues in the gas phase, in aqueous solution and in the dielectric medium within the minor groove have been determined by semiempirical calculations, by focusing on each dihedral angle connecting two rings in turn.

 

Rita Kakkar* & Ritu Garg

 

 

 

 

[[

 

 

 

1937

Synthesis of 5-arylidene-2-aryl-3-(1,2,4-triazolo-acetamidyl)-1,3-thiadiazol-4-ones as antibacterial, antifungal, analgesic and diuretic agents

1,2,4-Triazole on reaction with ethyl chloroacetate affords 1,2,4- triazoloacetate 1 which on treatment with N2H4 yields (acetohydrazido)-1,2,4-triazole 2. Condensation of 2 with various substituted aromatic aldehydes gives arylideneacetohydrazido-1,2,4-tri-azoles 3 which on cycloaddition with mercaptoacetic acid affords 2-(substituted aryl)-3-(1,2,4-triazolyl-acetamidyl)-4-oxo thiazolidines 4. Treatment of 4 with various substituted aromatic aldehydes furnish
5-arylidene-2-aryl-3-(1, 2, 4- triazolylacetamidyl)-1, 3-thiazolidin-4-ones 5. All the products have been screened for their antibacterial, antifungal, analgesic and diuretic activities.

 

 

S K Srivastava*, Soumya Srivastava &
S D Srivastava

 

 

 

 

 

Notes

 

 

 

 

 

 

1946

Bisazaheterocycles : Part VII - Synthesis of novel bisquinazolinonyl b-lactams

The synthesis of novel bisquinazolinonyl b-lactams as probes for multi-receptor sites is reported.

 

 

P S N Reddy*, P Pratap Reddy & T Vasantha

 

 

 

 

 

 

 

1950

Bisazaheterocycles : Part VIII -A new synthesis of 2,2-bisquinazolinones

A one step synthesis of 2,2-bisquinazolin-4(3H)-ones 4 from isatoic anhydride 1 and 2-hydrazinocarbonyl-3-methylquinazolin-4(3H)-ones 2 is reported.

 

P S N Reddy*, P Pratap Reddy & T Vasantha

 

 

 

 

 

 

 

 

1953

Synthesis of 3-[5-methyl-1-(4-methylphenyl)-1,2,3-triazol-4-yl]-6-substituted-s-triazolo[3,4-b]-1,3,4-thiadiazoles

 

Some novel s-triazolo[3,4-b]-1,3,4-thiadiazole derivatives 6a-i are reported.

 

 

 

Heng-Shan Dong*, Bin Quan & Jin-Dond Luo

 

 

 

 

 

1957

Synthesis of 3-methyl-4-[(chromon-3-yl) methylene]-1-phenylpyrazolin -5(4H)-ones and their conversion into 2-thio-5-hydroxy-5H-[1]-benzo-pyrano[4,3-d] pyrimidines

3-Methyl-4-[(chromon-3-yl) methylene]-1-phenylpyra-zolin-5(4H)-ones 3 have been prepared from the corresponding 3-formylchromones using base catalyst and are converted into 2-thio-5-hydroxy-5H-[1]-benzo-pyrano [4, 3-d] pyrimidines 6.

 

 

B K Karale*, C H Gill, Mohib Khan,
V P Chavan, A S Mane & M S Shingare

 

 

 

 

 

 

 

1960

Synthesis of 25-oxygenated D : A-friedoolean-anes: Part V* Conversion of putranjivadione (D : A-friedoolean-3, 7-dione) to 25-formyl D : A-friedoolean-3-one

Structure of the natural product 25-formyl D : A-friedoolean-3-one 1 has been established by its synthesis from putranjivadione 2.

 

S K Ghosh, S K Dutta, M Roy,
Kakoli Majumdar & Saktipada Das*

 

 

 

 

 

 

 

 

1962

Solvent-free synthesis of acyl thiosemicarbazides with microwave activation

A new and rapid synthesis of acyl thiosemicarbazides has been reported for the first time. Eight new acyl thiosemicarbazides have been synthesized in microwave oven. This approach needs only short reaction time (2~6 min) and gives excellent yields (86.0~94.5%).

 

 

Jian-Ping Li*, Qian-Fu Luo & Yu-Lu Wang

 

 

 

 

 

 

 

1964

Attempted synthesis of 2-azetidinones via ester enolate condensation reactions with imines and thioimidates

The condensation reaction of enolate of ethyl isobutyrate with azomethine systems has been used for the synthesis of 1, 2, 3 and 4.

 

 

 

 

 

S D Sharma*, Aarti Saluja, Susmita Bhaduri & Seema Kanwar

 

 

 

 

 

 

 

1970

Sodium borohydride-iodine, an efficient reagent for reductive amination of aromatic aldehydes

Reactions of aromatic aldehydes with primary amines give the corresponding secondary amines in the presence of iodine and sodium borohydride in methanol.

 

 

Ira Saxena, Ruli Borah & Jadab C Sarma*

 

 

 

 

 

 

 

 

 

1972

Selective removal of silyl protecting groups from hydroxyl functions with ammonium chloride in aqueous acetonitrile

Silyl ethers are efficiently hydrolyzed to their corresponding alcohols with NH4Cl in aqueous acetonitrile.

 

 

 

 

 

Ahmad Shaabani*, Ali Reza Karimi &
Ali Reza Alamshahi

 

 

 

 

 

 

 

 

 

 

1975

Hexamethylenetetramine-bromine complex (HMTAB) on wet silica: Oxidation of alcohols and sulfides

Secondary or benzylic alcohols and sulfides are converted into their corresponding carbonyl and sulfoxide compounds efficiently using wet silica supported HMTAB complex at room temperature.

 

 

 

 

 

Ahmad Shaabani*, Mohammad Bagher Teimouri & Ayoob Bazgir

 

 

 

 

 

 

 

 

 

 

1978

Synthesis and characterization of benzimida-zolylphenothiazine derivatives and a study of their antiviral and antifungal activities

Reaction of phenothiazine with p-aminobenzoic acid and aromatic aldehydes in ethanol furnishes 10-(a-p-carboxyphenylaminobenzyl) phenothiazines 2 which on treatment with o-phenylene diamine in pyridine results in the formation of 10-(a-p-benzimidazolyl-aminobenzyl) phenothiazines 3 in the yields varying from 60-85%. Antiviral and antifungal activities of 3 are reported.

 

 

 

 

Abha Bishnoi*, V K Pandey, Rashmi Saxena,
M N Joshi & S K Bajpai

 

 

 

 

 

 

 

 

 

 

1980

Some chemical constituents of Swertia chirata

In India, Swretia chirata Buch-Ham, commonly known as chirataya is used as a crude drug reported in Indian pharmacopoeia. One new compound characterized as nonacosanyl-hentriacontanoate 1 has been isolated from the aerial parts of Swertia chirata (Gentianaceae). Besides, two compounds stigmasterol 4 and 1,5-dihydroxy-3-methoxy-xanthone-8-O-b-d-glucopyranoside 2 have been isolated for the first time from this plant. During the chemical investigation of different extracts ten known compounds have also been isolated from Swertia chirata.

 

 

Nonacosanyl-hentriacontanoate, n =27

 

 

Neerja Pant, D C Jain* & R S Bhakuni

 

 

 

 

 

 

 

 

 

 

 

Authors for correspondence are indicated by (*)