Indian Journal of Chemistry

Sect. B: Organic Chemistry including Medicinal Chemistry Total visitors: 1,902  since 12-06-07

VOL. 46B

NUMBER 5

MAY 2007

CONTENTS

Papers

805

Total synthesis of (±)-b-microbiotene, (±)-micro­biotol, (±)-cyclocuparanol and (±)-b-cuparenones

IPC: Int.Cl.⁸ C07C

Total synthesis of the sesquiterpenes mentioned in the title has been described.

A Srikrishna* & D B Ramachary

818

4-Piperidone – A synthon for spiro-heterocycles

IPC: Int.Cl.⁸ C07D

A new class of spiro compounds piperidino-oxirane,
-cyclo­propane, -thiazolidone, -thiadiazole and
-thiazine have been developed from tetra substituted 4-piperidone adopting modern synthetic methodologies.

V Padmavathi*, T V Ramana Reddy&

K Audisesha Reddy

823

Synthesis of 2-indolylbenzimidazoles using Fischer’s indole method

IPC: Int.Cl.⁸ C07D

Treatment of substituted phenylhydrazines 5a and 5b with acetylbenzimidazoles 3 and 4 under Fischer’s indolization conditions give 2-benzimidazolyl indoles 9. Alternatively 9 can also be synthesized by the reaction of substituted indole-2-carboxylic acids 10a and 10b with substituted o-phenylenediamino sulphates 1a and 1b in refluxing ethylene glycol.

P K Dubey*, Balaji Babu & M Venkata Narayana

829

Phase transfer catalysed reaction of potassium superoxide with some nitroalkanes in the presence of a,b-unsaturated enones

IPC: Int.Cl.⁸ C07C

Superoxide ion, generated in situ by the phase transfer reaction of potassium superoxide and 18-crown-6 ether, brings about an easy Michael addition of nitroalkanes to a,b-unsaturated enones to afford 1,4-addition products.

Krishna Nand Singh*, Raghvendra Singh Raghuvanshi &

Manorama Singh

834

Regeneration of the carbonyl group in the hypervalent iodine oxidation of carbonyl derivatives of dehydroacetic acid and its analogues

IPC: Int.Cl.⁸ C07D

Hypervalent iodine oxidation of carbonyl derivatives of dehydroacetic acid and its analogues leads to a mild and efficient regeneration of parent carbonyl compounds leaving pyrone moiety intact.

Rashmi Pundeer, Vishwas Chaudhri,

Mayank Kinger & Om Prakash*

838

Chemical reactivity of 3-hydrazino-5,6-diphenyl-1,2,4-triazine towards p–acceptors activated carbonitriles

IPC: Int.Cl.⁸ C07D

Behaviour of 3-hydrazino-5,6-diphenyl-1,2,4-triazine 1 as electron donor towards different electron acceptors activated carbonitriles has been investigated and a novel fused heterocyclic system and 2,3-disubstituted 1,2,4-triazines have been obtained. Compound 1 reacts with 1,2-dicyanobenzene as p–acceptor in DMF to form bezencarboximidamide 16, while reaction of 1 with a-bromomalononitrile 17 in boiling DMF affords compound 18. On the other hand, compound 1 reacts with tetracyanoethane 23 in DMF to yield compound 24. The route of reaction in DMF indicate that charge–transfer complexation is the key intermediate to obtain new heterocyclic systems. Structures of the products are established by MS, IR, UV-Vis, CHN and ¹H NMR spectral data.

R M Abdel-Rahman & W R Abdel-Monem*

847

Chemical modifications of dehydrocostus lactone from Saussurea lappa and the study of structure-activity relationship

IPC: Int.Cl.⁸ A61K

Various chemical analogues of dehydrocostus lactone have been prepared using various chemo- and regio-selective reagents. The biological activity of the products as plant growth regulators has revealed that the extension of carbon chain length at C₁₃ to a limited extent has marked effect on biological activity.

R R Setia*, K Kaur, R Mankala & B R Chhabra

852

Synthesis and study of biological activity of some new 1,4-benzothiazines

IPC: Int.Cl.⁸ C07D

The synthesis of n-(4-methylpyrimidin-2-one-4-yl)-1,4-benzothiazine-2,3-dione 5¸2-thio-2,6-dimethyl­[1,3,5]­triazino[3,4-c]-1,4-benzothiazine 9, [1,2,4]-tri­azino-2-oxo-[3,4-c][1,4]-benzothiazine 13, 5-aryli­dene-1H-1,4-benzothiazine [1,3,4]triazole 16a-b, 2-thio-6-methyl[1,3,5]triazino[3,4-c]benzothiazine 19 N-(2-propanonyl)-1,4-benzothiazine-3(1H)-one 20 and tricyclic compound cyclopenteno-1,4-benzo­thiazine 21 have been reported and tested for anti­fungal and antibacterial activity.

M B Deshmukh*, S A Deshmukh, S S Jagtap &

A R Mulik

Notes

860

Synthesis and characterization of some alkoxy­phthalimide derivatives of benzotriazolylthia­dia­zoles and benzotriazolylthiazolidinones

IPC: Int.Cl.⁸ C07D

Some 5-(1,2,3-benzotriazol-1-yl-methyl)-N-alkoxy-phthalimido-1,3,4-thiadiazol-2-amines 5a-b and 2-[(1,2,3-benzotriazolyl)acetohydrazido]-3-N-alkoxy-phthalimido-5-arylidene-1,3-thiazolidin-4-ones 9a-h have been synthesized from 2-(1,2,3-benzotriazol-1-yl-acetate) hydrazine carbothioamide 3 using two different reaction routes. Compound 3 in turn is prepared by the reaction of benzotriazole 1 with ethylchloroacetate followed by condensation with thiosemicarbazide. Synthesized compounds are characterized by analytical and spectral studies.

Swati Ojha, Usha Ameta, Neelam Dhakar &

G L Talesara*

866

Microwave-assisted synthesis of substituted-4-oxo-4H-1-benzopyran-3-carboxaldehydes using Vilsmeier reagent over silica gel

IPC: Int.Cl.⁸ C07D

Substituted-4-oxo-4H-1-benzopyran-3- 3- carboxalde­hydes 2 have been synthesised in  good yields under microwave irradiation  using Vilsmeier reagent over silica gel in  solvent free conditions.

Poonam Kamotra, Avinash K Gupta &
Rajive Gupta*

869

Synthesis of 3-(6-aryl-pyridin-2-yl)- and 8-(6-aryl-pyridin-2-yl) coumarins

IPC: Int.Cl.⁸ C07D

Mannich bases of 3-acetyl coumarin 1 and 4-methyl-7-methoxy-8-acetyl coumarin 4 on reaction with substituted phenacyl bromide pyridinium salts 2a-f in the presence of ammonium acetate in refluxing acetic acid afford the title 3-(6-aryl-pyridin-2-yl)- and 8-(6-aryl-pyridin-2-yl) coumarins 3a-f and 5a-f in moderate to good yields.

D I Brahmbhatt*, J M Gajera, V P Pandya &

M A Patel

872

A new flavone glycoside from Zanthoxylum acanthopodium DC

IPC: Int.Cl.⁸ C07D

Examination of the dry fruits of Zanthoxylum acan­tho­podium has led to the isolation of a new flavone glycoside along with herbacetin-8,4'-dimethyl ether. The new flavone glycoside is characterized as 7-O-a-d-glucosyl-3,8-dihydroxy-2-(3-hydroxy-4-methoxy­phenyl)-5-methoxy-4H-1-benzopyran-4-one on the basis of its spectral studies and that of its aglycone. This is the first report of the isolation of 5-O-substituted flavone from the genus Zanthoxylum.

B Ravindra Babu, Shilpi Khurana,

Rajeev Sakhuja, Amit K Srivastava & Subhash C Jain*

875

Synthesis and fungicidal activity of some 3-(5-aryl-1,3,4-thiadiazol-2-yl)-1-(ß-d-glucopyrano­syl)-5-alkyl-2-thio-4-imidazolidinones

IPC: Int.Cl.⁸ C07D

Alok Kumar Srivastava, R K Khare* & H Singh

880

Synthesis and bioactivity of some new [3-[4-methylphenoxymethyl]-4-phenyl-[1,2,4]­triazole-5-thio]acetanilide derivatives

IPC: Int.Cl.⁸ C07D

The synthesis of some triazole derivatives starting from 4-methyl-phenoloxyacetyl hydrazide is described. The title compounds have been found to enhance root elongation.

Tai-Bao Wei, Jing Tang, Hong Liu & You-Ming Zhang*

884

Synthesis and antimicrobial activity of some new 2-substituted aminothiazoles

IPC: Int.Cl.⁸ C07D

Amino group of thiazole has been treated with various aromatic aldehydes to get the corresponding Schiff bases  (SMB-2 to SMB-9). These Schiff  bases have been reacted with chloracetyl  chloride to get the corresponding  azetidinones. Compounds SMB-1,  SMB-2 and SMB-6 show good  antibacterial and antifungal activity.

Bhavin Sutariya*, S K Raziya, S Mohan &
S V Sambasiva Rao

Authors for correspondence are indicated by (*)

IPC: International Patent Classification

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