Indian Journal of Chemistry

Sect. B: Organic Chemistry including Medicinal Chemistry

Total visitors: 2,898  since 16-04-08

VOL. 47B

NUMBER 3

MARCH 2008

CONTENTS

Papers

411

Stereochemistry and stereodynamics of N-chloroacetyl-r-2,c-6-diarylpiperidin-4-ones - NMR studies and semi-empirical molecular orbital calculations

Six N-chloroacetyl-r-2,c-6-diarylpiperidin-4-ones are found to exist in equilibrium between boat conformations B1 and B2 in solution and gaseous states.

M Venkatraj*, S Ponnuswamy & R Jeyaraman

427

Studies on novel polycyclic heterocycles: synthesis of new naphthaquinoxaline and naphtha­zaquino­xaline derivatives from naturally occurring quinones

A facile synthesis of novel polycyclic heterocycles is carried out by the reaction of lapachol and β-lapachone, naturally occurring naphthoquinones with o-phenylene diamine and 2,3-diaminopyridine leading to the formation of naphthaquinoxaline and naphthazaquinoxaline deri­vatives. Regioselectivity in the reaction of β-lapachone with 2,3-diaminopyridine is confirmed by single crystal X-ray diffraction study.

Pahup Singh*, Anshu Dandia &

Poonam Khandelwal

434

An efficient, inexpensive ‘Green Chemistry’ route to multicomponent Biginelli condensation cataly­zed by CuCl₂.2H₂O-HCl

Vijai Nath Pathak*, Ragini Gupta &

Bindu Varshney

439

Synthesis of some new 2-(3-methyl-7-substituted-2-oxoquinoxalinyl)-5-(aryl)-1,3,4-oxadiazoles as potential non-steroidal antiinflammatory and analgesic agents

The present study reports the multistep synthesis of unknown 3-methyl-7-substituted-1-{[5-(aryl)-1,3,4-oxadia­zol-2-yl]methyl}­quinoxalin-2(1H)-ones, and 3-methyl-7-sustituted-1-{[5-(alkylsulfanyl)-1,3,4-oxadiazol-2-yl]­me­th­yl}­quinoxalin-2(1H)-ones and evaluation of their anti-inflammatory and analgesic activities.

Shivananda Wagle, Airody Vasudeva Adhikari* & Nalilu Suchetha Kumari

449

Enantiospecific synthesis of thaps-8-en-5-ol via stereospecific intramolecular chirality transfer

Enantiospecific synthesis of thaps-8-en-5-ol, starting from (R)-carvone, has been accomplished.

A Srikrishna* & K Anebouselvy

460

Evaluation of anticancer activity of some 1,3,4-oxadiazole derivatives

Carboxymethyl derivatives of various para substi­tuted/unsubstituted oxadiazole-2-thione have been evaluated for their potential anticancer activity.

Pinaki Sengupta, Deepak Kumar Dash,

Veerendra C Yeligar, K Murugesh,

D Rajalingam, Jagadish Singh & T K Maity*

463

Synthesis of some new 5-[2-{(1,2,3-benzotriazole)-1- yl-methyl}- 1¢-(4¢-substituted aryl-3¢-chloro-2¢-oxo azetidine)]-amino-1,3,4-thiadiazoles: Anti­­­fungal and antibacterial agents

As a part of systematic investigation of synthesis and biological activity, several new 5-[2-(1,2,3-benzotriazole)-1-yl-methyl]–arylidine hydrazino–1,3,4–thiadiazoles 7 and 5-[2-{(1,2,3-benzotriazole)-1-yl-methyl} -1¢-(4¢-substituted aryl-3¢-chloro-2¢-oxo-azetidine]-amino-1,3,4- thiadiazoles 8 have been synthesized from 5-[2-(1,2,3-benzotriazole)-1-yl-methyl]-5-hydrazino-1,3,4-thiadiazoles 6 using 1,2,3-benzotriazole as the starting material. All the synthesized products are evaluated for their antifungal activity against Aspergillus niger, Aspergillus flavus, Fusarium oxisporum and Trichoderma viride and antibacterial activity against Bacilus subtilis, Escherichia coli, Klebsiella pneumoneae and Staphylococcus aureus. The structure of all the synthesized compounds have been determined by spectral and chemical methods.

D K Shukla & S D Srivastava*

Notes

470

Lupeol ester from Clerodendrum phlomidis L.

A new triterpene ester, together with tetratriacontanol and 24β-ethylcholesta-5,22E,25-triene-3β-ol, has been isolated from the aerial parts of Clerodendrum phlomidis L. Occurrence of a triterpene fatty acid ester lup-20(29)-en-3-triacontanoate in this plant is of taxonomic importance. Structures of all the isolated compounds have been established by spectroscopic and chemical studies.

R Pandey, R Kaur, R Malasoni & M M Gupta*

473

Synthesis and characterization of some novel isoxazoles and 1,5-benzothiazepines bearing s-triazine nucleus

Chalcones, 2,4-bis-(phenylamino)-6-[4′-{3′′-(substituted phenyl)-2′′-propenon-1′′-yl}-phenyl amino]-s-triazines 6a-d have been prepared from ketone 5 carrying s-triazine nucleus. These chalcones 6a-d on cyclisation with hydroxy­lamine hydrochloride and 2-aminothiophenol give the corresponding isoxazoles 7a-d and 1,5-benzo­thiazepines 8a-d, respectively. They are characterized by elemental analysis, IR, ¹H NMR and LCMS data.

Anjani Solankee*, Kishor Kapadia,

Pankit Solankee, Yogesh Prajapati, Hiral Patel & Sejal Solankee

477

Synthesis and antimicrobial activity of some new pyrazolo[3,4-d]pyrimidines and thiazolo[4,5-d]­pyri­midines

Various 3-isopropyl-4-aryl-1,4,5,7-tetrahydropyrazo­lo_­[3,4-d]pyrimidin-6-ones 4a-d and 7-aryl-6,7-dihydro-3H,4H-thiazolo[4,5-d]pyrimidine-2,5-diones 7a-d have been synthesized from 5-isopropyl-2,4-dihydro-3-pyrazolone 1 and 2,4-thiazolidine 5 respectively in two steps. All newly synthesized compounds have been fully characterized by elemental analysis, IR, ¹H NMR and mass spectral data. The antimicrobial activity of all compounds has been evaluated.

where, R = 4-OCH₃, 2-OCH₃, 3,4-(OCH₃)₂

J D Akbari, K B Mehta, S J Pathak &

H S Joshi*

481

Yttrium triflate-catalyzed reactions of indoles with electron-deficient olefins

The reaction condition for Michael addition of indoles to a series of electron-deficient olefins catalyzed by Y(OTf)₃ has been carefully optimized at ambient temperature and the reaction affords the corresponding Michael adducts in good to excellent yields with high selectivity. Y(OTf)₃ is also found to be able to catalyze the Michael addition of furan.

Liangdong Sun, Changshui Gao, Weiyi Zhou & Yuping Wei*

485

Synthetic potentiality of α-chloronitrone in alde­hyde synthesis: A new approach

N-Phenyl-N-cyclohexyl-α-chloronitrones have  been syn­the­sized and  a new method of synthesis of aldehyde has been discovered involving SNⁱ and SN² reactions with benzyl chloride

Bhaskar Chakraborty* &

Manjit Singh Chhetri

Authors for correspondence are indicated by (*)