Indian Journal of Chemistry

Sect. B: Organic Chemistry including Medicinal Chemistry

VOL. 40B

NUMBER 7

JULY 2001

CONTENTS

Advances in Contemporary Research

 

 

 

550

InCl3 in organic syntheses

 

 

Rina Ghosh

A review on the use of InCl3 in organic syntheses has been described.

 

 

 

Papers

 

 

 

 
558

Synthesis of novel 2,6-disubstituted-3-amino-4-trifluoromethylfuro[2,3-b]pyridines

 

 

 

 

 

 

 

 

 

 

 

 

 

 

K Srinivas, B Narsaiah*, P Shanthan Rao &

J Madhusudana Rao

A series of novel 2-acyl or benzoyl-3-amino-4-trifluoromethyl-6-substituted furo [2,3-b]pyridines have been synthesised from 4-trifluoromethyl-6-substituted-1,2-dihydro-2-oxo-3-pyridine carbonitrile via 2-O-phenacyl or acetonyl-3-cyano-4-trifluoromethyl-6-substituted pyridines.

 

 

 

 

 

 

 
565

Studies on the syntheses of 2-phenylsulphonyl-3-styrylquinoxaline

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

V S H Krishnan, K S Chowdary,

P K Dubey* & S Vijaya

2-Phenylsulphonyl-3-styrylquinoxaline 6 has been prepared by the reaction of sodium benzenesulphinate with the corresponding 2-chloro-3-styrylquinoxaline 4. An alternate method for the preparation of 6 from 2 through the intermediacy of 7 is also described.

 

 

 

 

 

574

Selective solvomercuration of dienes: Synthesis of olefinic mercuric chlorides, iodides and hydroxides

 

 

 

 

 

 

 

 

 

 

 

 

Navdeep Kaur & Ranjit S Dhillon*

One pot selective solvomercuration of dienes using mercuric acetate in  dry MeOH followed by, in situ, treatment with NaCl or KI or NaOH of mercurinium intermediate at 0°C afford, in good yields, the olefinic mercuric chlorides, iodides and hydroxides, respectively.

 

 

 

 

 

 

 

 

 
579

Tetraethylammonium bromide catalysed phase transfer reaction of potassium superoxide with hydrazones and tosylhydrazones

 

 

 

 

 

 

 

 

 

 

 

 

 

Rajesh Kumar & Krishna Nand Singh*

Various hydrazones and tosylhydrazones on reaction with potassium superoxide in the presence of tetraethylammonium bromide are efficiently transformed to azines or olefins in fairly good yields.

 

 

 

 

 

 

 
584

Heterocyclic systems containing bridgehead nitrogen atom: Synthesis, stereochemistry and evaluation of biological activity of thiazolo[3,2-b]-s-tetrazines and trans-dihydro­pyrazolo[3¢,4¢:4,5]thiazolo[3,2-b]-s-tetra­zines

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Jag Mohan

3,3-Diethyl-2H,4H-thiazolo[3,2-b]-s-tetrazin-6(7H)-one 2, 3,3-diethyl-2H,4H-6,7-dihydrothiazolo[3,2-b]-s-tetra­zine hydrobromide 4 and 6-aryl-3,3-diethyl-2H,4H-thia­zolo[3,2-b]-s-tetrazine hydrobromide 5 have been synthesised by the reaction of 6,6-diethyl-1,2,4,5-tetrahydro-s-tetrazin-3-thione 1 with chlolroacetic acid, 1,2-dibromo­-ethane and a­-haloketones, respectively.

 

 

 

 

 

 

 

 

 

 

587

QSAR with electrotopological state atom
index: Part II
¾ Antimalarial activity of dihydroqinghaosu derivatives

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Kunal Roy*, Dipak Kumar Pal,

Achintya Saha & Chandana Sengupta

Quantitative Structure Activity Relationship study and antimalarial activity of some ester and ether derivatives (AR1-AR21) of dihydroqinghaosu (dihydroartemisinin) with electrotopological state atom index reveals the importance of the oxygen atoms (including those of the peroxide bridge) of artemisinin skeletal ring structure and the lactol oxygen for the activity. The results are in good agreement with the previous reports on the pharmacophoric requirements of artemisinin analogs obtained by other QSAR techniques.

 

 

 

 

 

 

 

 
596

Justicia lignans: Part 9 ¾ Two new lignans from Justicia neesii Ramamoorthy (white flower variety)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Kovuru Gopalaiah, Jakka Kavitha,

Raju V Kanumuri, Dodda Rajasekhar &

Gottumukkala V Subbaraju*

Two new lignans (1 and 2) have been isolated from J. neesii and characterised by spectral data and chemical transformations. 2 is the first neolignan from Justicia species.

 

 

 

 

Notes

 

 

 

601

Synthesis of novel pyrazolino[4¢,3¢:6,7]-cyclohept[b]indoles

 

 

C Kavitha & K J K J Rajendra Prasad*

Treatment of 2-benzylidene-1-oxo-1H-2,3,4,5-tetra-hydrocyclohept[b]indole derivatives 1a-e with hydrazine hydrate affords the pyrazolino[4¢,3¢:6,7]cyclohept-[b]indoles 2a-e.

 

 

 

 

 

 
603

Studies on the synthesis of 6-(substituted pyridyl)-2H-[1,4]benzoxazin-3(4H)-one deriva-tives

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

V S H Krishnan, K S Chowdary,

P K Dubey*, A Naidu & S Vijaya

Condensation of 2 with a variety of chalcones 3 gives 6-(substituted pyridyl)-2H-[1,4]benzoxazin-3(4H)-one 4. Formation of 4 from 2 is explained mechanistically. Studies on alkylation of 4a to obtain 5 is also described.

 

 

 

 

 

 

 

 
608

Synthesis of 2,6-dimethyl-4-substituted pyridine-3,5-dicarbonitriles from b-amino-acrylonitriles

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

F Al-Omran* & A A El-Khair

2,6-Dimethyl-4-substituted pyridine-3,5-dicarbonitriles 2a-c have been obtained from b-aminoacrylonitriles and aldehydes. Condensation of 2a-b with DMF/DMA affords N,N-dimethylaminobenzaldehyde 8a-c.

 

 

 

 

 

 

 

 

 
612

Synthesis of triazones in aqueous media under microwave irradiation

 

 

 

 

 

 

 

 

 

 

 

 

 

Saeed Balalaie* & Arash Shokrollahi

Three component condensation of N,N¢-dimethylurea, aqueous formaldehyde and primary amines under microwave irradiation leads to triazones 4 in high yields.

 

 

 

 

 

 
614

Synthesis of C7-C16-alkyl glycosides. Part I ¾ Synthesis of alkyl d-xylopyranosides in the presence of tin(IV) chloride as a Lewis acid catalyst

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Stanimir Konstantinović, Zorica Petrović,

Aleksandra Spasojević & Biljana Mojsilović

The Lewis acid catalyzed glycosylation reaction of b-peracetylated sugar derivative (xylose) with fatty alkanols is used in a synthesis of C7-C16-alkyl xylopyranosides. The process occurs under the influence of tin(IV) chloride.

 

 

 

 

 

 

 
619

Hypervalent iodine mediated solid state synthesis of 1,8-naphthyridinyl-1,3,4-oxadiazoles

 

 

 

 

 

 

 

 

 

K Mogilaiah* & P Raghotham Reddy

An efficient and convenient conversion of acylhydrazones 2 to 1,3,4-oxadiazoles 3 using iodobenzene diacetate (IBD) in the solid state is described.

 

 

 

 

 

 

 

 

622

Reductions using LiCl/NaBH4: A rapid and efficient cleavage of organic disulfides to mercaptans

 

 

 

S Raja Ram, K Purushothama Charry &

D S Iyengar*

A practical and novel reagent system LiCl/NaBH is used for the reductive cleavage of organic disulfides to mercaptans under mild conditions in excellent yields.

 

 

 

 

 

 

 

 
625

Pd(II)-promoted base hydrolysis of 2-cyano-1,10-phenanthroline

 

 

 

 

 

 

 

 

 

S Ghammami, S Derakhshan,

A R Mahjoub & A Soudi*

Pd(II)-promoted base hydrolysis of 2-cyano-1,10-phenanthroline has been studied.  The reaction is first order each in metal-substrate complex and in hydroxide ion. The mechanism of metal-catalysed addition involves one step external attack rather than attack by nucleophile from the metal coordination sphere.

 

 

 

 

 

 

 
628

Some unusual observations in the synthesis of benzofuran based nor-neolignan

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Atulya K Panda & M R Parthasarathy*

Attempted synthesis of 1 involving Vilsmeier-Haack reaction leads to the product 8. The unusual observations encountered during this have been recorded.

 

 

 

 

 

 

 

632

Micelle catalysed methylene blue reduction by ascorbic acid: A procedure for the determination of vitamin C in pharmaceutical samples

 

 

 

Kaushik Mallick, Anjali Pal &

Tarasankar Pal*

A simple, cost-effective and direct determination of ascorbic acid (vitamin C) in pharmaceutical preparations is reported using cationic micelle (CTAB) immobilised methylene blue as the reagent.

 

 

 

 

 

 

 

 
636

Synthesis and antimicrobial study of heterocyclyl substituted s-triazoles,1,3,4-thiadia-zoles, oxadiazoles and related heterocycles

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A M Dhiman, K N Wadodkar* &

S D Patil

Synthesis of various heterocycles 3,4,5,6 and 7 are described from substituted thiosemicarbazides 2. Some of these reported heterocycles are assayed for their antibacterial activity.

 

 

 

 

 

 

 
640

Synthesis and antimicrobial study of some bridgehead nitrogen heterocycles

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A M Dhiman, K N Wadodkar* & S D Patil

3-Substituted-4-amino-5-mercapto-s-1,2,4-triazoles 2a-d are subjected to the action of various reagents to get some different bridgehead nitrogen heterocycles, such as 3a-d, 4a-d, 5a-d and 6a-d. All these reported compounds have been secreened for their bactericidal nature.

 

 

 

 

 

 

 

 
644

Two new limonoids from Polygonum orientale L.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Jiaming Liu

Isolation and identification of two new limonoids polygonumin A 3 and polygonumin B 4 from Polygonum orientale L.

 

 

 

 

 

 

Authors for correspondence are indicated by (*)

 

 

 

 

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