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Five types of troponoids including 40 molecules were prepared by means of palladium(0)-catalyzed carbonylation and successive acylation or benzoylation after immobilization of 2-methoxy-5-trifluoromethylsulfonyloxytropone on solid support. Four types of them showed mesophases. The final products have enough purity to detect their mesomorphic properties.

A liquid crystalline library of 100 molecules with three benzene rings and 18 molecules with two benzene rings was synthesized on solid support by means of benzoylation or acylation and palladium(0)-catalyzed carbonylation of a secondary amine obtained by a reductive amination of 4-iodoaniline and a backbone amide linker. The conversion and purity of the final products are high enough to investigate the mesomorphic properties.

The phenacyl esters of peptide segments were efficiently cleaved by zinc reduction using a chelating compound, acetylacetone, in the presence of pyridine.

A synthesis of kifunensine ( 1 ) has been achieved by a route involving, as a key step, a double cyclization of aldehyde 3 with ammonia.

A stereoselective kinetic protonation of the azetidinone enolate B was studied and an efficient synthesis of2(cis) was achieved via aldol reaction of 5 with acetone followed by the kinetic protonation with Ph3SnH as proton source.

The syntheses of FR-33289 (3), originally isolated from a microorganism, and FR-32863 (6), first designed on the basis of a biogenetic consideration and recently found to be also present in nature, are described.

An efficient stereospecific synthesis of optically active 4-allylazetidinones ( 6 , 7 , 11 , and 15a,b ) has been accomplished using silver-promoted coupling reaction of allylsilanes 5 and 14b with 4-chloroazetidinones ( 3 , 4 , and 10a,b ) derived from penicillins.

A total synthesis of (+)-castanospermine (2) has been achieved starting from D-mannose by a route adopting a double-cyclization process (5c→6) as the key step.

An efficient method for selective amino acid protection with proper differentiation between the two amino acid groups in meso-2,2′-diaminopimelic acid has been achieved [ 7 → 8 → 9 → 10 → 11 ] and applied to the synthesis of FK-156 [ 10 → 12 → 14 → 1 ].

A new, efficient synthesis of the optically active carpetimycins 1 from penicillins has been achieved via, as key steps, aldol reaction of isonitrile 19 , followed by n-Bu3SnH reduction.

The structure of WF 3681 ( 1 ), an aldose reductase inhibitor isolated from a Chaetomella species, has been determined on the basis of its physical and chemical properties and confirmed by a total synthesis.

Aldol and alkylation reactions of the chiral 4-allylazetidinone 1 gave 3,4-trans-azetidinones as major products, in which 10 was converted in several steps to the optically active 6-epicarpetimycins 2.

The structure of the immunomodulator FR 900483 (C5H9NO3) has been shown to be 1 on the basis of chemical and spectroscopic evidence and confirmed by a synthesis from D-glucose.