Indian Journal of Chemistry

Sect. B: Organic Chemistry including Medicinal Chemistry

Total visitors: 3,477  since 12-06-07

VOL. 46B

NUMBER 6

JUNE 2007

CONTENTS

Communications

 

 

 

975

Synthesis of conformationally constrained a-imino acid derivatives via ring-closing metathesis

Conformationally constrained a-imino acid derivatives have been prepared via ring-closing metathesis. Attempts to achieve the synthesis of nine-membered imino acid derivative resulted in the formation of dimeric, 18-membered macrocyclic bis-a-imino acid derivative.

 

 

 

 

 

 

Sambasivarao Kotha* & Priti Khedkar

 

 

 

 

 

Papers

 

 

 

980

Microwave-assisted synthesis and biological activity of 3-alkyl /aryl-6-(1-chloro-3,4-dihydro­naphth-2-yl)-5,6-dihydro-s-triazolo [3,4-b] [1,3,4] thiadiazoles

3-Alkyl / aryl-6-(1-chloro-3,4-dihydronaphth-2-yl)-5,6-di­hydro-s-triazolo [3,4-b][1,3,4]thiadiazoles 3 have been synthesised under microwave irradiation and have been screened for their antibacterial, antifungal, antiinflammatory and antioxidant activity.

 

 

 

 

 

 

Poonam Kamotra, Avinash K Gupta,

Rajive Gupta*, P Somal & S Singh

 

 

 

 

 

 

 

 

 

 

 

 

 

985

Coumarin dimer and sesquiterpene lactones from Carpesium lipskyi Winkl

A new coumarin dimer Carpesilipskyin 1 and two new sesquiterpene lactones, carabrol isovalerate 2 and 2'-hydroxy-4',6'-dimethoxy-benzoylcarpesiolin 3 have been isolated from Carpesium lipskyi Winkl.

 

 

 

 

 

 

 

 

Jian Nong Wang*, Shi Ping Gu & Ren XiangTan

 

 

 

 

 

 

 

989

Copper-catalyzed substitution reactions of acylal with organomanganese reagents

In the presence of Me3Si-Cl, Cu(NCMe)4[BF4] and Cu(NCMe)2 (PPh3)2[BF4] complex shows remarkable catalytic activity in substitution of one acetate group of aromatic acylal to form esters in high yield.

 

 

 

 

  

 

 

 

 

 

Madhukar B Deshmukh, Sunil D Jadhav* &

Shashikant V Kadam

 

 

 

 

 

 

 

 

 

 

 

 

995

A novel approach to 12-chloro-3-thio-4H-quino[3,2-e][1,3]diazocines via Vilsmeier Haack reaction

The Vilsmeier Haack reaction on 4-hydroxy­quinaldines leads to a potential intermediate 4-chloro-3-formyl-2-(2-hydroxy-ethene-1-yl)quino­lines. The inter­mediate is further utilized to prepare quino[3,2-e][1,3]diazocines on treatment with thio urea.

 

 

 

 

 

 

R Nandha Kumar, T Suresh, T Dhanabal &

P S Mohan*

 

 

 

 

 

 

 

1001

Do the electronic effects of sulfur indeed control the p-selectivity of g-sulfenyl enones? Further evidence

The reductions of g-sulfenyl and g-sulfonyl enones with NaBH4 and LiAlH4 lead to highly reduced anti-to-S selectivity. The selectivity turns even syn-to-S in some instances. These results underline the significance of steric effects arising from the steric bulk of the reducing agent and the substituent on S and negate any substantial role of the electronic effects of S on the observed diastereocontrol as reported previously.

 

 

 

 

 

 

 

K Ganesh Babu & Veejendra K Yadav*

 

 

 

 

 

 

 

1004

Synthesis and 1H and 13C NMR spectral study of some t(3)-aryl-r(2),c(4)-dicarbalkoxy-c(5)-hydroxy-t(5)-methylcyclohexanones and their oximes

Eight t(3)-aryl-r(2),c(4)-bis(carbalkoxy)-c(5)-hydroxy-t(5)-methylcyclohexanone oximes 4a-11a have been synthesised and use of 13C and 1H chemical shifts for determining the configuration and conformation of oximes is also discussed.

 

 

 

 

S Amirthaganesan, R T Sabapathy Mohan,

K Murugavel, G Muthukumaran & K Pandiarajan*

 

 

 

 

 

 

 

 

 

 

 

 

1014

Synthesis of some 1,3,4-oxadiazole derivatives as potential anti-inflammatory agents

The synthesis of some new 1,3,4-oxadiazole derivatives and 1,2,4-triazine-5-one has been described. IR, 1H NMR and mass spectral data support the structures of newly synthesized compounds. The compounds, which show good anti-inflammatory activity, have been screened for their ulcerogenic and lipid peroxidation activities.

 

 

 

Mohd Amir*, S A Javed & Harish Kumar

 

 

 

 

 

 

1020

Naphthalene azomesogens with terminal chloro groups

A homologous series of azomesogens, with terminal chloro groups have been synthesized. All the homologous synthesized compounds exhibit enantiotropic nematic mesophase. The mesomorphic properties of the present series are compared with other structurally related series to evaluate the effect of terminal chloro group and its position on mesomorphism.

 

 

B T Thaker*, D M Patel & P K Tandel

 

 

 

 

 

 

 

 

Notes

 

 

 

1025

Synthesis of a,a'-bis (arylmethylidene) cyclo­alkanones catalyzed by molecular iodine: An improved procedure for the Claisen-Schmidt condensation

Molecular iodine efficiently catalyzes the two-component condensation of cycloalkanones and aldehydes to afford the corresponding a,a'-bis (arylmethylidene) cycloalkanones. The new protocol for the Claisen-Schmidt condensation reaction works well in the absence of the solvent. The yields are high and reactions go to completion in 10-15 min under mild condition.

 

 

 

 

 

 

M A Päsha* & V P Jayäshankara

 

 

 

 

 

 

1028

The anion recognition of simple-structure molecular tweezers receptors based on acyl-thiourea

Some compounds have been designed and snthesized in high yields as novel simple anion receptors. They have high selectivities for F and AcO. The binding properties for anions of the receptors have been examined by UV-vis and 1H NMR spectroscopy. They showed that 1:1 stoichiometry complexes are formed between the receptors and the anions through hydrogen bonding interactions in DMSO solution.H NMR

 

 

 

Tai-bao Wei, Wei Wei, Cheng Cao & You-ming Zhang*

 

 

 

 

 

 

 

1033

Synthesis of 2-aminophenyl-5-phenyl-4-[3-oxo-1,4-benzoxazin-6-yl] thiazoles as potential COX-2 inhibitors

A series of 2-amino phenyl-5-phenyl-4-[3-oxo-1,4-benzoxazin-6-yl]thiazoles 5a-n have been prepared and evaluated for their COX-2 inhibition activity.

 

 

 

 

 

 

T Venkateshwar Kumar, K Srinivasa Rao, P K Dubey*,
K Anil Kumar & P Reddanna

 

 

 

 

 

 

 

 

 

 

 

 

1038

Unusual KMnO4 oxidation product of b-ionone

The structure of hydroxyionolactone 3 obtained by KMnO4 oxidation of b-ionone 1 is supported by spectral data and confirmed by single crystal X-ray diffraction of bromolactone 8.

 

 

Shrivallabh P Kamat*, Asha M D’Souza,
Shashikumar K Paknikar, Mohan M Bhadbhade & Rajesh G Gonnade

 

 

 

 

 

 

 

1042

3D-QSAR analysis of cycloguanil derivatives, highly active agents against A16V + S108T mutant of dihydrofolate reductase resistant strain (T9/94) of Plasmodium falciparum

A 3D-QSAR analysis based on the compounds reported in the literature has been performed to derive mathematical (Hansch analysis) model, which can be effectively used to design and predict the activity of the new cycloguanil derivatives to have activity against resistant strains.

 

 

 

Vineet Singh & Meena Tiwari*

 

 

 

 

 

 

 

1047

Solventless synthesis of 2,4,10a-triaryl-1,10a-dihydro-2H-pyrazino[2,1-b][1,3] benzoxazole

A solventless synthesis of 2,4,10a-triaryl-1,10a-dihydro-2H-pyrazino[2,1-b][1,3] benzoxazole has been achieved in good yield by the reaction of 2-[(2-oxo-2-arylethyl)anilino]-1-aryl-1-ethanones with 2-aminophenol in p-toluenesulfonic acid.

 

 

 

 

 

G Ravindran, S Muthusubramanian*,
S Selvaraj & S Perumal

 

 

 

 

 

Authors for correspondence are indicated by (*)

IPC: International Patent Classification

Int.Cl8.: International Classification, 8th Edition, 2006