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Cyclopropanation of the ester group in ethyl 3-chloropropanoate and subsequent cleavage of the three-membered carbocycle in intermediate 1-(2-chloroethyl)cyclopropyl methanesulfonate gave 2-bromomethyl-4-chlorobut-1-ene, and the latter was used as key intermediate in the synthesis of racemic ipsenol and ipsdienol which are components of Ips typographus L. European spruce spark beetle pheromone.

Epoxidation of 2-cyano-2,3-seco-24-nor-4(23)-ene derivatives of oleanolic acid with m-chloroper­oxy­benzoic acid, followed by treatment of the resulting epoxides with boron trifluoride–diethyl ether complex, afforded new 24-noroleanane derivatives whose structure was determined using two-dimensional NMR correlation techniques (1H–1H COSY, 1H–1H NOESY, 1H–13C HSQC, 1H–13C HMBC). Depending on the conditions, the reaction of methyl 2-cyano-2,3-seco-24-norolean-4(23)-ene-28-oate with m-chloroperoxybenzoic acid may be regioselective with the formation of 4(23)-epoxy or 12-oxo derivative, as well as allylic oxidation product of the isopropenyl moiety.

Intramolecular electrophilic cyclization of 6-allylsulfanylpurine by the action of iodine and arenesulfenyl chlorides gave 7-iodomethyl-7,8-dihydro[1,3]thiazolo[2,3-i]purin-6-ium pentaiodide and 7-arylsulfanylmethyl-7,8-dihydro[1,3]thiazolo[2,3-i]purin-6-ium perchlorates, respectively. 7-Iodomethyl-7,8-dihydro-[1,3]thiazolo[2,3-i]purin-6-ium iodide reacted with sodium and potassium alkoxides to produce alkyl N-[5-(4-methyl-1,3-thiazol-2-yl)-1H-imidazol-4-yl]formimidates, and its reaction with secondary cyclic amines afforded 5-(4-methyl-1,3-thiazol-2-yl)-N-[morpholin-4-yl(or piperidin-1-yl)methylidene]-1H-imidazol-4-amines. Successive treatment of 7-arylsulfanylmethyl-7,8-dihydro[1,3]thiazolo[2,3-i]purin-6-ium perchlorates with sodium acetate and morpholine led to the formation of 5-(4-arylsulfanylmethyl-4,5-dihydro-1,3-thiazol-2-yl)-N-(morpholin-4-ylmethylidene)-1H-imidazol-4-amines.

The possibility was studied of using levoglycosenone in the synthesis of N-(glucosen-2-yl) aminides. New glucosaminides were obtained containing the residues of L-a, isopinocampheol, borneol,, and (-)-(1S,2R,3S,7S,8R)-4,4-dimethyl-3-nitro-9,11-dioxatricyclo[6.2.1.02,6]-undec-5-en-7-ol.

A highly regioselective ring opening reaction of terminal epoxides with 2-bromobenzoic acid catalyzed by tetrabutylammonium bromide was accomplished. The procedure is operationally simple and practical for the synthesis of a series of β-hydroxy esters. Using this protocol, oxetan-3-ol could be prepared efficiently in a good yield.

Epoxy derivatives of 3-methylenecyclobutane-1-carbonitrile and methyl 3-methylenecyclobutane- 1-carboxylate undergo isomerization into the corresponding 3-hydroxymethylbicyclobutane-1-carboxylic acid derivatives on treatment with lithium diisopropylamide in aprotic medium.