title: Synthesis of protected purpurosamine B and 6-epipurpurosamine B.
abstract: In relation to the synthesis of antipseudomonal drugs, namely, gentamicin C2 and 3-de-O-methylsporaricin A, a protected purpurosamine B (15) and 6-epipurpurosamine B (13) were synthesized. The key intermediate, methyl 2,3,4,7- tetradeoxy-6-O-(methylsulfonyl)-2-phthalimido-beta-L-lyxo-++ +heptopyranoside (8), was obtained in 48% yield by Grignard addition to methyl 2,3,4-trideoxy-2-phthalimido-alpha-D-erythro-hexodialdo-1,5-pyrano side (7) proceeding in accordance with Cram's chelate rule, followed by methylsulfonylation. From 8, compound 15 was readily obtained by introduction of the azide group with inversion of configuration at C-6. Compound 13 was obtained by introduction of the azide group with retention of configuration.
authors.forename: N
authors.initials: N
authors.lastname: Yasuda
authors.forename: K
authors.initials: K
authors.lastname: Matsuda
authors.forename: H
authors.initials: H
authors.lastname: Tsutsumi
authors.forename: T
authors.initials: T
authors.lastname: Takaya
mesh_terms: D000900:Anti-Bacterial Agents / Q000138:chemical synthesis*; D006539:Heptoses / Q000138:chemical synthesis* / Q000494:pharmacology; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D009904:Optical Rotation; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D013329:Structure-Activity Relationship
chemical_list: D000900:Anti-Bacterial Agents; D006539:Heptoses; D007202:Indicators and Reagents; C048282:purpurosamine B; C048283:6-epipurpurosamine B