Indian Journal of Chemistry

Sect. B: Organic Chemistry including Medicinal Chemistry

Total visitors: 4,147  since 05-09-08

VOL. 47B

NUMBER 9

September 2008

CONTENTS

Papers

1397

Synthesis of biologically active 3-(2-oxo-2H-benzopyran-6-yl)-2-(-2-oxo-2H-benzopyran-6-ylimino)-thiazolidin-4-one and its derivatives

Vinata V Mulwad* & Sagar A Mayekar

1402

A mild and versatile synthesis of bis(indolyl)methanes and tris(indolyl)alkanes catalyzed by antimony trichloride

Antimony trichloride is found to be a mild and efficient catalyst for electrophilic substitution reaction of indole derivatives with a variety of carbonyl compounds in acetonitrile to afford the corresponding bis(indolyl)-methane in excellent yield. a,b-Unsaturated aldehydes give tris(indolyl)alkane under the same reaction condition.

Pradip Kundu & Gourhari Maiti*

1407

The reactions of polyhalogenated-2-nitro-1,3-butadiene with alkylthio, thiomorpholine and piperazine derivatives

Mono(thio)substituted-1,3-nitrodiene compounds 3a-c give 5a, 5c, 7a, 7c, 9a, 9c, 11a, 11c, 13a, 13b with thiomorpholine 4 and piperazine derivatives 6, 8, 10, 12. The new compound 3a is synthesized from reaction of 1 with 2a. The compound 7b crystallizes in the monolinic crystal system (space group P2_1/n) with the n-butyl group attached to S1 and C2Cl3 group disordered. The butadiene unit is not completely planar as can be expected if the two double bonds are fully conjugated. The structure has been solved by direct methods by using SHELXS-97 program and refined by using SHELXL-97 to the residul index R₁= 0.048.

Cemil Ibis* & N Gulsah Deniz

1414

Enantiospecific synthesis of (+)-trans-a-himachalene via an intramolecular type II carbonyl ene reaction

Enantiospecific synthesis of (+)-trans-a-himachalene, starting from (R)-carvone, has been accomplished.

A Srikrishna* & P Ravi Kumar

1423

Construction of spiro[4.5]decane via ring-closing metathesis reaction: Formal synthesis of acorone and isoacorones

Two approaches for formal synthesis of spirosesquiterpenes acorones have been described.

A Srikrishna* & M Srinivasa Rao

Notes

1430

Titanocene(III) chloride mediated radical-induced synthesis of 3,4-disubstituted tetrahydrofurans: Formal synthesis of (±)-burseran and (±)-dehydrocubebin

Sinthesis of 3,4-disubstituted tetrahydrofurans has been achieved via radical cyclization of epoxides using titanocene(III) chloride (Cp₂TiCl) as a transition-metal radical source. The radical initiator (Cp₂TiCl) is generated in situ from commercially available titanocene dichloride (Cp₂TiCl₂) and zinc dust in THF under argon. Formal synthesis of two bioactive lignans, burseran and dehydrocubebin has also been accomplished through the radical technology.

S Jana, M Paira & S C Roy*

1435

Synthesis of p-tert-butylcalix[8]arene ether derivatives

2a : R = -CH3	2b : R = -C2H5	2c : R = C3H7	2d : R = -C4H9
2e : R = -C5H11	2f : R = -C6H13	2g : R = -C8H17

Jianmin Yi, Kewen Tang*, Saijin Huang &
Kelong Huang

1438

Synthesis and antibacterial activity of 6-(5-phenyl-[1,3,4]thiadiazol-2-ylamino)-benzopyran-2-ones

Sagar A Mayekar & Vinata V Mulwad*

1443

Studies on synthesis of unsymmetrical 2,2¢-bisbenzimidazole sulphides of pharmacological interest

The synthesis of 2-(a-thioethyl-2¢-benzimidazolyl)- benzimidazole 3 by alternative routes is described.

R=H, CH₃, OCH₃, NO₂, Cl

P K Dubey*, A Naidu, P V V Prasada Reddy,
N D Mahesh Kumar & B George Vineel

1447

The structure of Hantzsch coumarin

The dimethyl dicoumarin prepared by Hantzsch and Zurcher has been characterized as 4,6-dimethyl-2H,8H-benzo[1,2-b:4,5-b’]dipyran-2,8-dione by unambiguous synthesis of both angular and linear pyranocoumarins by Wittig reaction promoted by clay and comparing them with authentic Hantzch coumarin prepared as described in literature. This is the first record of synthetic proof for the structure of Hantzch coumarin

P Ramesh*, Anoop T Das, P Mohandass &

R Nagasathya

1451

Synthesis and pharmacological activities of novel furobenzopyrone and benzofuran derivatives

The reactions of 2-cyanoacetohydrazide and 2'-acetyl -2-cyano-acetohydrazide with each of furobenzopyrone derivatives 1a-d and benzofuran derivatives 10a,b have been studied. The antimicrobial and antiinflammatory activity of the new compounds have also been evaluated.

E R El-Sawy*, Kamel H Shaker, A H Mandour,
A Shehab El-Din & M M Abdula

1463

An efficient synthesis of 1,5-benzodiazepines catalysed by GaCl₃ under solvent free conditions

Various 1,5-benzodiazepine derivatives have been synthesized from o-phenylenediamines and ketones using catalytic amount of GaCl₃ (5 mol%) under solvent free conditions. This method is facile, efficient, environmentally benign and affords 1,5-benzodiazepines in excellent yield.

Sanjay Kumar & Jagir S Sandhu*

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