[reaction: see text]. The zirconium-mediated intramolecular ester transfer reaction of N-alkenyl carbamate derivatives proceeded to give alpha-substituted gamma-aminobutyric acid (GABA) derivatives in good to excellent yields. Quenching experiments of the reaction mixture with iodine or O2 indicated the presence of a cyclopropane intermediate. The resulting iodide was converted to 2-substituted pyrrolidine-3-carboxylate and/or alpha-alkylidene-gamma-aminobutyric acid derivatives in a stereospecific manner.

The Weill-Marchesani syndrome is a rare systemic connective tissue disease characterised by small stature, brachydactyly, ectopia lentis, and spherophakia. Three siblings with typical manifestations of this syndrome were reported. The ophthalmological findings in all these cases were spherophakia, severe myopia, a shallow anterior chamber, and narrow angle glaucoma. Two cases underwent laser iridotomy and drug treatment. In the third case the lens was removed from the eye because of injury, and this lens was examined by light and electron

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Reactions of organo-metal compounds Reactions of organo-metal compounds O 0350Construction of Nitrogen-Heterocyclic Compounds Through Zirconium-Mediated Intramolecular Alkene-Carbonyl Coupling Reaction of N-(o-Alkenylaryl)carbamate Derivatives. -The outcome of the reaction between N-(o-alkenylaryl)carbamates and zirconocene complexes strongly depends on the nature of the N-substituent. Thus, N-benzyl derivatives undergo convenient ring closure to afford fused lactams. In contrast, starting from N-tosyl derivatives, only desulfonylation and/or ester transfer products are obtained. Aliphatic N-benzyl carbamates predominantly undergo decomposition. -(TAKIGAWA, Y.; ITO, H.; OMODERA, K.; ITO, M.; TAGUCHI*, T.; Tetrahedron 60 (2004) 6, 1385-1392; Sch. Pharm., Univ. Pharm. Life Sci., Hachioji, Tokyo 192, Japan; Eng.) -Jannicke 22-080 2004 Reactions of organo-metal compounds

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D i a s t e r e o s e l e c t i v e I n t r a m o l e c u l a r E s t e r T r a n s f e r R e a c t i o n o f N -A l k e n y l c a r b a m a t e D e r i v a t i v e s Abstract: Zirconium-mediated diastereoselective alkene-carbonyl coupling reactions of N-alkenylcarbamate derivatives are reported. The present alkene-carbonyl coupling reactions using chiral tertbutyl 3-butenylcarbamates having a substituent at the homoallylic position proceeded in a highly diastereoselective manner to give a-methyl-g-substituted g-aminobutyric acid (GABA) derivatives. Iodination of the intermediary zirconium species gave the a-iodomethylated g-aminobutyrates, which were, in turn, converted to the 5-substituted pyrrolidine-3-carboxylate having cis stereochemistry.

Aminocarboxylic acids (hydrazinocarboxylic acids) and esters P 0270Diastereoselective Intramolecular Ester Transfer Reaction of N-Alkenylcarbamate Derivatives Mediated by Zirconocene-Butene Complex: Preparation of α,γ-Disubstituted γ-Aminobutyric Acid (GABA) Derivatives and 2,4-Disubstituted Pyrrolidine Derivatives. -(TAKIGAWA, Y.; ITO, H.; OMODERA, K.; KOURA, M.; KAI, Y.; YOSHIDA, E.; TAGUCHI*, T.; Synthesis 2005, 12, 2046-2054; Sch. Pharm., Univ. Pharm. Life Sci., Hachioji, Tokyo 192, Japan; Eng.) -Nuesgen 51-058