Indian Journal of Chemistry

Sect. B: Organic Chemistry including Medicinal Chemistry

VOL. 41B

NUMBER 6

JUNE 2002

CONTENTS

 

 

Papers

 

 

1226

A mechanistically designed cinchona alkaloid ligand in the osmium catalyzed asymmetric dihydroxylation of alkenes

A new ligand has been designed using dihydroquinine as the chiral controller for asymmetric dihydroxylation of alkenes. The purpose of this design of the ligand is to find out the transition state involved in the mechanism of asymmetric dihydroxylation, which may shed some light to differentiate between the hypothesis put forward by Sharpless’ and Corey’s groups. The present study supports the hypothesis proposed by Sharpless et al. and it appears that the L shaped cleft may be involved in governing the high selectivity of asymmetric dihydroxylation of alkenes.

 

 

 

 

B B Lohray*, S K Singh & V Bhushan

 

 

 

 

 

 

 

 

 

 

1234

A convenient synthesis of 3,5-diarylthieto[2,3-d] thiazole-2-thiones, and expansion of their thiete ring with carbon disulphide

 

 

 

 

L D S Yadav*, Suman Dubey & Smita Singh

 

 

 

 

 

 

 

 

 

1238

Syntheses, characterisation and fluorescence study of some novel naphthalimide derivatives

Some new fluorescent derivatives viz. 4-tosylamido-1,8-naphthalic anhydride 4, 4-dansylamido-1,8-naph-thalimido-N-pentanol 7 and 4-dabsylamido-1,8-naph-thalimido-N-pentanol 8 have been prepared and characterised. Their comparative fluorescence study and quantum yield has been carried out in various solutions and in the presence of different ions and buffers. These can be used for covalent labelling of different biomolecules.

 

 

Yashveer Singh, Arvind Misra &
Krishna Misra*

 

 

 

 

 

 

 

 

 

 

1246

Covalent labelling at 5˘-end of synthetic oligonucleotides by one step generation of alkylamino group

 

 

Krishna K Dubey, Yashveer Singh,
Sanjay Kumar, Ramendra K Singh &
Krishna Misra*

 

 

 

 

 

 

 

1251

An efficient method for selective deprotection of trimethylsilyl ethers, tetrahydropyranyl ethers, ethylene acetals and ketals under solvent-free conditions

 

Abdol R Hajipour*, Shadpour E Mallakpour*,
I Mohammadpoor-Baltork & S Khoee

 

 

 

 

 

 

 

1257

Synthesis and antibacterial activity of N-bridged heterocycles derived from aryloxymethyltriazoles

Reactions of aryloxymethyltriazoles have been described. The resulting N-bridged heterocycles have been characterized and their antibacterial activities are studied.

 

B Shivarama Holla*, K Shridhara &
M K Shivananda

 

 

 

 

 

 

 

 

1263

Synthesis of some of the antibacterial compounds from 4-hydroxycoumarins: Part II

Synthetic utility of 1 to synthesize various biologically active heterocycles like 2-6 has been reported.

 

V V Mulwad* & J M Shirodkar

 

 

 

 

 

 

 

1268

QSAR with electrotopological state atom index : Part IV Receptor binding affinity of proges-tagens

 

 

 

 

 

 

 

 

Achintya Saha*, Kunal Roy, Kakali De & Chandana Sengupta

QSAR analysis of receptor binding affinity of progestagens with electrotopological state atom index has been performed in an attempt to locate the pharmacophore fragment of the molecules.

 

 

 

 

 

 

1276

Chemical examination of the Echinoderms of the Indian Ocean : The triterpene glycosides of the sea cucumbers : Holothuria nobilis, Bohadschia aff. tenuissina and Actinopyga mauritana from Lakshadweep, Andaman and Nicobar Islands

Three new artificial genins (1, 1a and 2) along with seven known genins (3-9) have been obtained from acid hydrolysis of triterpenoid glycosides of the sea cucumbers.

1  R = OH                                                                              2

1a R = H

 

Parvataneni Radhika, Vallurupalli Anjaneyulu, Potluri Venkata Subba Rao*,
T N Makarieva* & A I Kalinovosky

 

 

 

 

 

 

 

1283

Pterocarpan, phenol and lipid constituents from Butea monosperma stem

In addition to stigmasterol-3-al-arabinopyranoside, four new compounds isolated from the stems of Butea monosperma have been characterized as 3-methoxy-8, 9-methylenedioxypterocarp-6-ene, 21-methylene-22-hydroxy-24-oxooctacosanoic acid methyl ester, 4-pentacosanylphenol and pentacosanyl-b d-glucopyrano-side by spectral data and chemical studies.

 

1                                                                     4             

2                                             

 

Y N Shukla*, Mamta Mishra & Sushil Kumar

 

 

 

 

Notes

 

 

 

1286

Facile one-pot synthesis of 2-aminothiazoles from 1,3-diazabuta-4-methylthio-1,3-dienes

Convenient synthesis of 2-aminothiazole derivatives from reactions of 1,3-diazabuta-1,3-dienes with thioglycolic acid and ethyl bromoacetate are described.

 

Paramita D Dey, Arun K Sharma, Jayakumar S & Mohinder P Mahajan*

 

 

 

 

 

 

 

1290

Synthesis of new Schiff base p-tert-butyl-calix[4]arene with imine units spanning 1,3-distal positions on the lower rim

 

Manoj Kumar*, Vandana Sharma nee˘ Bhalla & Neerja Sharma

 

 

 

 

 

 

 

 

1293

Oxidative coupling of thiols to disulfides by piperazinium dichromate

Aliphatic and aromatic thiols can be oxidized to the corresponding disulfides in the presence of piperazinium dichromate under mild condition.

 

 

 

B Movassagh*, M M Lakouraj* & K Ghodrati

 

 

 

 

 

1296

Facile preparation of amides from thioamides by ceric ammonium nitrate

Ceric ammonium nitrate has been  used to convert thioamides into amides in aqueous acetic acid under very mild conditions.

 

 

Barahman Movassagh*, Forhatosadat Meibodi & Shahin Sobhani

 

 

 

 

 

 

 

1299

InCl3 mediated reactions of aldehydes with allyltrimethylsilane

InCl3 mediated coupling reactions of aromatic aldehydes with allyltrimethylsilane readily provide the respective homoallylalcohols and/or the substituted pyran derivatives.

 

Rina Ghosh*, Arijit Chakraborty, Debasish De & Swaraj B Maiti

 

 

 

 

 

 

 

1302

Selective regeneration of carbonyl compounds from aldoximes and ketoximes, catalyzed by FeCl3 and SeO2

An oxidative deblocking procedure of aldoximes using FeCl3 and ketoximes using SeO2 in aprotic solvent is reported. Reaction yields are competitive as compared to previous methods. Reactions are easy to work and conditions are mild. Some important features of FeCl3 are mentioned.

R1 = alkyl, aryl, heteryl.

R2 = H, When (a),

R2 = alkyl, aryl When (b).

 

 

R V Hangarge, A S Mane, V P Chavan &
M S Shingare*

 

 

 

 

 

 

 

 

1305

Studies on aroylation of o-phenylenediamine and subsequent reactions with electrophiles

Condensation of o-phenylenediamine 1 with benzoyl chloride gives a dibenzoyl derivative 2 irrespective of the molar ratios employed.  However, with arylsulphonyl chlorides, a 1:1  (i.e. 3) or 1:2 (i.e. 4) products are obtained depending on the molar ratios used. Reaction of 3 independently with aromatic aldehydes  and acetonylacetone result in the formation  of 5 and 6 respectively.

 

P K Dubey*, Subhash M Kulkarni & R Vinod Kumar

 

 

 

 

 

 

1310

Substituted pyrazolines and their cardiovascular activity

1,3-Diphenyl-2-propen-1-ones (chalcones) 3 on reaction with thiosemicarbazide yield 1-thiocarbamoyl-3, 5-diphenyl-2-pyrazolines 4.  3 on condensation with arylisothiocynate give 1-N substituted thiocarbamoyl-3,5-diphenyl-2-pyrazolines 5. Compounds 3c, 5b, 5c, 5d, 5h, 5i, 5j exhibit potent cardiovascular and higher ALD50 activity.

 

Vineet Malhotra, Seema Pathak, Rajendra Nath, Devashis Mukerjee & Kripa Shanker*

 

 

 

 

 

 

 

1314

Synthesis and biocidal activity of 2-aryl/aryl-oxymethyl-1,3,4-oxa/thiadiazolo[4,5-b][1,2,4]tri-azolo[5,4-c]thiazolo-spiro-7-cyclohexanes

2-Aryl / aryloxymethyl-1, 3, 4-oxa/thiadiazolo[4,5-b] [1,2,4]triazolo[5,4-c]thiazolospiro-7-cyclohexane (4 and 8) have been synthesised by cyclisation of 3-[2-aryl/aryloxymethyl-1, 3, 4-oxa/thiadiazol-5-yl]imino-spiro (cyclohexane-1,2-thiazolidin-4-ones) (3 and 7) with conc. H2SO4 in cold. All compounds have been assayed for their fungicidal activity against Pyricularia oryzae, Pseudopersonospora cubansis, Sphaerotheca fulginea, Phytophthora infestans and Puccinia coronata.

 

Nizamuddin*, Shafqat Alauddin, H C Gupta & Manoj Kumar Srivastav

 

 

 

 

 

 

 

 

 

1319

The flavonoids from Polygonum aviculare

A new flavonoid has been isolated from Polygonum aviculare, together with five known flavonoids.

 

 

Li-Ping Sun*, Shang-Zhen Zheng,
Jin-Xin Wang, Xu-Wei Shen, Xu-Dong Zheng

 

 

 

 

 

 

 

 

 

 

1321

A new tetracyclic phenol and other constituents from the roots of  Bauhinia racemosa

The roots of Bauhinia racemosa  Lamk. (Fam. Caesalpinioideae) afford lupeol, betulin and b-sitosterol along with a novel tetracyclic phenol. The latter is identified as 3-hydroxy-de-O-methyl racemosol by comparative spectral studies with racemosol and de-O-methyl racemosol isolated earlier from this plant.

 

 

 

 

Renuka Jain*, Shahla Alam & Umesh Saxena

 

 

 

 

 

 

 

Authors for correspondence are indicated by (*)