Stereoselective synthesis of the hydroxy amino acid moiety of Al-77-B, a gastroprotective substance from Bacillus pumilus Al-77
✍ Scribed by Akiyoshi Kawai; Osamu Hara; Yasumasa Hamada; Takayuki Shioiri
- Publisher
- Elsevier Science
- Year
- 1988
- Tongue
- French
- Weight
- 222 KB
- Volume
- 29
- Category
- Article
- ISSN
- 0040-4039
No coin nor oath required. For personal study only.
✦ Synopsis
The hydroxy amino acid moiety of AI-77-B (1) has been prepared as its protected form 2 from the (R)-glyceric acid derivative 3 in an efficiently stereoselective manner through the direct C-acylation using diphenyl phosphorazidate and the hydroxy-directed hydrogenation.
Al-77-B having a unique gastroprotective activity has been isolated from a culture broth of Bacillus pumilus Al-77 and its absolute stereostructure 1 has been determined by Shimojima and co-workers.4 The unique structure 1 can be constructed from the dihydroisocoumarin part A and the hydroxy amino acid side chain B. We report herein a highly stereoselective synthesis of the protected form 2 of the hydroxy amino