Chemistry and antimicrobial activity of caryoynencins analogs.
Caryoynencins (1) are antibiotics isolated from liquid cultures of a plant pathogen, Pseudomonas caryophylli, and are unstable C18 carboxylic acids with a conjugated dienetetrayne structure. Enyne analogs of caryoynencins were synthesized from monosilylated 1,3-butadiyne 2 (n = 2), 1,3,5-hexatriyne 2 (n = 3), and 1,3,5,7-octatetrayne 2 (n = 4) by alkynyl metal addition to 2,4-hexadienal (3) followed by allylic rearrangement and deprotection. Tetraynol 5 (n = 4) thus obtained was resolved by enzyme reactions. The conjugated dienetetrayne compounds are mixtures of 3E,5E- and 3E,5Z-isomers, which equilibrate by room light. 13C-NMR chemical shifts of polyynes obey simple rules, which can be used for signal assignments. Antimicrobial activities of conjugated enynes and related compounds were examined. The tetrayne analog 6 (n = 4) possesses potent antibacterial and antifungal activities, while triyne and diyne analogs 6 (n = 3 and 2) are less active. Chirality does not affect the activities. An isomeric enyne compound, 2,4-tetradecadiene-7,9,11,13-tetrayn-6-ol (8), showed potent activity against Tricophyton.
Department of Chemistry, Graduate School of Science, Tohoku University, Japan.
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M
Yamaguchi
H J
HJ
Park
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Ishizuka
K
K
Omata
M
M
Hirama
D000480:Alkynes / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D000935:Antifungal Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects; D009682:Magnetic Resonance Spectroscopy; D008826:Microbial Sensitivity Tests; D003904:Mitosporic Fungi / Q000187:drug effects; D009089:Mucor / Q000187:drug effects; D011549:Pseudomonas / Q000737:chemistry*; D013329:Structure-Activity Relationship
D000480:Alkynes; D000900:Anti-Bacterial Agents; D000935:Antifungal Agents