Rapid Communications

1688

A convenient enantiospecific methodology for (-)-(1R, 5S)-1,5-dimethylbicyclo­[3.3.0]­octa-2,7-dio­ne: A formal total synthesis of (-)-ceratopicanol

An enantiospecific formal total synthesis of the sesquiterpene ceratopicanol is described.

A Srikrishna*, N Chandrasekhar Babu & Dattatraya H Dethe

Papers

1691

Synthesis of Fmoc-/Boc-/Z-β-amino acids via Arndt-Eistert homologation of Fmoc-/Boc-/Z-α-amino acids employing BOP and PyBOP

A simple and efficient protocol for the synthesis of Fmoc-/Boc-/Z-α-aminod iazoketones using BOP or PyBOP as a coupling agent is described.

G R Vasanthakumar & V V Suresh Babu*

1696

Facile synthesis of oligonucleotides on solid support using pyridine derivatives for amino and phosphate protection

The picolinoyl group has been used for amino protection on nucleosides: dC, dA, & dG. The compatibility of this group has been checked during solid phase synthesis of two oligomers, viz. d(TACGTTTTGCT) and d(ACCGATATCGT). The compositions of these oligomers have been confirmed by their enzymatic hydrolysis with SVPD and SPD.

Sarika Sinha & Ramendra K Singh*

1701

Preparation of 4-(1-alkyl-benzo[d]imidazole-2-yl)-2-phenyl-2,3-dihydrobenzo(b)[1,4]­thia­ze­pines

The preparation of benzimidazolyl-2-benzothiazepins 6 involving the condensation of o-aminothiophenol with benzimidazole chalcone 5 followed by dehydrogenation with Cu(OAc)₂/chloranil yielding 4 is described.

P K Dubey*, A Naidu, C Ravi Kumar &
P V V Prasada Reddy

1706

Acetoxylation reactions of 17a,21-dichloro-20-oxopregnanes and their relatives

Acetoxylation reactions of 17a, 21- dichloro -20 –oxo­pregnanes and their relatives under different conditions using anhydrous sodium and potassium acetate are being studied in order to produce cortisone or triamcinolone side chain.

Saroj Hazarika, Papori Goswami &
Pritish Chowdhury*

1711

¹H NMR spectral study of some 2,6 –diphenyl­thian-4-ones and their 1,1-dioxides^†

The uses of Altono’s equation and DAERM method in calculating proton-proton torsional angles have been compared using the vicinal proton-proton coupling constants of three thianes and their corresponding 1,1-dioxides.

K Pandiarajan* &
J Christophor Newton Benny

1716

The role of orbital symmetry  in Bergman cyclization

AM1 investigation on two model systems show that Bergman cyclization is a symmetry controlled thermally allowed reaction.

Sandip Kumar Kundu, Twishasri Das Gupta, Suven Das & Animesh Pramanik*

1723

Synthesis of some new benzothia/oxazepinyl indoles as an antipsychotic agents

Several 3-(2¢-substitutedaryl-3¢-substitutedarylamino­me­thy­lene-2¢,3¢-dihydro-1¢5¢-benzothia/oxazepin-4¢-yl)indo­les and 3-(2¢-substitutedaryl-3¢-substitutedarylazo-2¢,3¢-dihydro-1¢,5¢-benzothia/oxazepin-4¢-yl)indoles have been synthesized and tested for their antipsychotic  activity.

Kiran Bajaj, V K Srivastava, S Lata,
Ramesh Chandra & Ashok Kumar*

1729

Isoxazolinyl derivatives of anthranilic acid as antiinflammatory agents

Synthesis of 5-substituted-N-[4¢-(substitutedphenyl)­amino­­­ethyl-5¢-(substitutedphenyl)isoxazolin-2¢-yl]anthra­nilic acids is reported.

Preeti Rani, V K Srivastava &
Ashok Kumar*

1734

Synthesis and antibacterial activities of newer  derivatives of pyrido[2,3-d; 6,5-d¢]dipyrimidines

R Nandha Kumar, T Suresh & P S Mohan*

Notes

1738

Studies in Hantzsch thiazole synthesis: Synthesis of 3-(2-allylamino-4-thiazolyl)-2H-1-benzopyran-2-ones and 3-(4-phenyl­thia­zoline-2-anil)-2H-1-benzopyran-2-ones in solid state

Interaction of 3-(2-bromoacetyl)coumarins with N-allyl­thiourea and diphenyl thiourea in solid state furnish corresponding 3-(2-allylamino-4-thiazolyl)-2H-1-benzo­pyran-2-ones and 3-(4-phenylthiazoline-2-anil)-2H-1-benzo­­pyran-2-ones.

P Vijaykumar, R Vinod Reddy &
 V Rajeswar Rao*

1742

A facile one step synthesis of fused isoxazolo-[4,5-b]pyridine-N-oxides

Reaction of 3,5-dimethyl-4-nitroisoxazole 1 with alkyl and aralkyl ketones gives unexpected and interesting fused isoxazolo[4,5-b]pyridine-N-oxides 2 whose structures could be known only through X-ray diffraction. They are deoxygenated to pyridines 3 by treatment with PCl₃.

T Jagan Mohana Chary, A Krishna Murthy & E Rajanarendar*

1746

Synthesis of some novel azetidino [2,3-b] [1,8]naphthyridin-2(1H)-ones and 1,2,4-tria­zolo [4,3-a][1,8] naphthyridines

Synthesis of 1-arylazetidino[2,3-b][1,8]naphthyridin-2(1H)-ones 3 and 1-aryl-4-carbethoxy-1,2,4-triazolo [4,3-a][1,8] naphthyridines 6 starting from ethyl 1,8-naphthyridin-2-one-3-carboxylate 1 has been described.

K Mogilaiah*, P Raghotham Reddy,
R Babu Rao & N Vasudeva Reddy

1750

Microwave assisted addition-elimination re­act­ions of 3-phenylimino-2-indolinones with 2-hydrazino-3-(p-chlorophenyl)-1,8-naph­thy­ri­dine: A simple and facile synthesis of 3-(3-p-chlorophenyl-1,8-naphthyridin-2-ylhydrazono)-2-indolinones

Addition-elimination reactions of 3-phenyl-imino-2-indolinones 2 with 2-hydrazino-3-(p-chlorophenyl)-1,8-naphthyridine 1 under microwave irradiation have been described.

K Mogilaiah*, S Kavitha & H Ramesh Babu

1753

Microwave assisted synthesis of pyrazolo[3,4-b]quinolines containing 1,8-naphthyridine moiety

1,8-Naphthyridinylpyrazolo[3,4-b]quinolines 4 have been synthesized by reaction of 2-hydrazino-3-(4-methoxy­phenyl)-1,8-naphthyridine 1 with 2-chloroquinoline-3-carbaldehydes 2 followed by cyclization with DMF/KOH under microwave irradiation.

K Mogilaiah*, G Rama Sudhakar &
N Vasudeva Reddy

1756

Microwave-assisted synthesis and biological activities of some bridge-head nitrogen heterocycles

Reaction between 1 and different aromatic aldehydes 2 in the presence of p-TS-OH using microwave irradiation affords the compounds 3a-v. All the products have been evaluated for their antimicrobial activity against several microbes.

H M Hirpara, V A Sodha, A M Trivedi,
B L Khatri & A R Parikh*

1760

Synthesis of 2-iminothiazolidines through reaction of N-arylsulphonylaziridines with isothiocyanates in the presence of iodide ions

Reaction of 2-substituted N-arylsulphonylaziridines with isothiocyanates using lithium iodide as a catalyst yields iminothiazolidines.

U K Nadir* & Susan Joshi

1765

Benzimidazolium dichromates : Efficient reagents for selective oxidation of alcohols
to carbonyl compounds

Oxidation of alcohols with benzimidazolium dichromates in acetic acid at RT results in the formation of carbonyl compounds with good selectivity and high yields.

K Ramaiah, P K Dubey*, J Ramanatham ,
C Ravi Kumar  & J S Grossert

1768

Reductive dicyclization of α,β-unsaturated ketones promoted by Sm and catalysed by HgCl₂

Jiming M  Zhang & Yongmin M Zhang*

1771

Reductive cleavage of the Te-Te bond in ditellurides by CeCl₃/Sm system: A novel method for the synthesis of b-telluroesters (and nitriles)

Diaryl ditellurides are reduced by CeCl₃/Sm system to produce the aryltellurolates which react smoothly with a,b-unsaturated esters (and nitriles) to give b-telluroesters (and nitriles) in moderate to good yields.

Xue li, Songlin Zhang*, Yulu Wang & Yongmin Zhang

1774

Rapid cleavage of azo compounds to amine/s using Raney nickel and ammonium formate or formic acid

Azo compounds are reductively cleaved to corresponding amine/s catalyzed by Raney nickel using ammonium formate at room temperature.

D Channe Gowda*, Shankare Gowda &
K Abiraj

1777

A rapid and efficient method for acetylation of phenols with acetic anhydride catalysed by TiO₂/SO₄^2-solid superacid

A rapid and efficient method for acetylation of phenols with acetic anhydride in the presence of TiO₂/SO₄^2-solid superacid at room or at reflux temperature in excellent yield is described.

Yan-Ran Ma, Tong-Shou Jin*,
Zhen-Hua  Wang & Tong-Shuang Li

1779

Synthesis and antibacterial activity of amoenylin, a metabolite of Dendrobium amoenum

Amoenylin 6, has been synthesised from syringaldehyde 1 in three steps with an overall yield of 40%.

Somepalli Venkateswarlu,
Marellapudi S Ramachandra & Gottumukkala V Subbaraju*

1782

Terpenoid and lipid constituents from Artemisia annua   

Two new minor compounds, a bisnor cadinane 1 and the other lipid constituent 3 have been isolated from Artemisia annua. Their structures have been determined by IR, EIMS 1D & 2D NMR and their physicochemical studies.

                 CH₃CH₂CH₂-CH-CH=CH-CH-CH-(CH₂)₉-COCH₃

                                                                                                                                                                                                     ‌                        ‌        ‌

                                                                                                                                OH                  OH  OH

Amit Tewari & Rajendra Singh Bhakuni*

1786

Components from whole plant of Phyllanthus amarus Linn

Secosterols named as amarosterol A, characterized as 13,14-seco-stigma 5(6), 14(15)-diene-3-a-ol 1 and amarosterol B, characterized as 13,14-seco-stigma 9(11), 14(15)-diene-3-a-ol  2 have been isolated from whole plant of Phyllanthus amarus.

Bahar Ahmad* & Tanveer Alam

Authors for correspondence are indicated by (*)