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threo-γ-Hydroxy-L-β-lysine which is a constituent amino acid of antibiotics tuberactinomycin A and N, was synthesized from threo-β-hydroxy-L-ornithine derivative by the Arndt-Eistert reaction. The synthetic amino acid was identical with the natural sample in all respects. Furthermore, a route was established to prepare a protected γ-hydroxy-β-lysine derivative useful for the peptide synthesis.

Lepidopteran, self-defence substance produced by silkworm (Bombyx mori), was synthesized by the solution method for confirmation of the proposed structure.

Bulgecinine, a new proline type amino acid in bulgecins, was synthesized stereospecifically by use of D -glucose as a chiral precursor.

( S )-(+)-α-Methylserine and γ- l -glutamyl- l -arginine were isolated from Sphagnum palustre . This is the first isolation of α-methylserine from the plants.

The chemical structure of E. coli lipid A was elucidated to be 2 by determination of the nature of the individual acyl groups bound to the two hydroxyl groups in positions 3,3′ and the two amino groups of the D-glucosamine disaccharide phosphate backbone.

Synthesis of threo-3-methyl-D-cysteine, a moiety of β-methyllanthionine as a component of the peptide antibiotics nisin and subtilin, was achieved via (2R,3R)-1-t-butoxycarbonyl-3-methyl-2-aziridinecarboxamide derived from D-threonine. An addition of thioacetic acid or thiobenzoic acid to the aziridinecarboxamide gave S-acyl-β-mercapto-α-amino acid amide derivatives which were hydrolyzed directly or after the preformation of disulfide bond to afford the desired amino acid.

An acylated tetrasaccharide phosphate 1 was synthesized and identified with the corresponding natural derivative obtained from LPS of E. coli Re mutant by cleavage of the glycosidic phosphate group. The proposed structure of the natural Re LPS was thus confirmed.

The dehydroxymethyl analog of bulgecin A was synthesized in order to establish a synthetic route of bulgecin A.

The structure of lanthiopeptin, a new lanthionine peptide effective against Herpes virus, was newly determined. It has a unique tetracyclic sequence which is very similar to but different from the proposed structure for Ro 09-0198. However, Ro 09-0198 was found to be quite the same compound as lanthiopeptin in all respects.

Dibenzyloxycarbonyl- and di-t-butyloxycarbonyl-L-β-lysine were synthesized from corresponding diacyl-L-ornithine by modified Arndt-Eistert reaction involving diazoketone preparation via the mixed carbonic carboxylic anhydride. These diacyl-β-lysine derivatives are required for total- or semi-syntheses of peptide antibiotics, tuberactinomycins or streptothricins.

A new spider toxin NSTX-3 was chemically synthesized for confirmation of the proposed structure and use in the investigation of neuroscience.

Optically active carnosadine, a new cyclopropyl amino acid from red alga Grateloupia carnosa , was synthesized and its absolute structure was determined.

Tuberactinomycin O, one of the four congeners of the antituberculous peptide tuberactinomycin, was totally synthesized. The β-ureidodehydroalanine moiety was constructed from β, β-diethoxyalanine with excess urea in acidic medium after a cyclization reaction of a pentapeptide was finished. Cyclization was carried out by means of the 1-succinimidyl ester method. To the cyclic pentapeptide, β-lysine was introduced as the branched moiety and then deprotected to afford tuberactinomycin O which was completely identified with the natural form of the antibiotic.