First total syntheses of (Z)-15-methyl-10-hexadecenoic acid and the (Z)-13-methyl-8-tetradecenoic acid.
The first total syntheses for the (Z)-15-methyl-10-hexadecenoic acid and the (Z)-13-methyl-8-tetradecenoic acid were accomplished in seven steps and in 31-32% overall yields. The (trimethylsilyl)acetylene was the key reagent in both syntheses. It is proposed that the best synthetic strategy towards monounsaturated iso methyl-branched fatty acids with double bonds close to the omega end of the acyl chain is first acetylide coupling of (trimethylsilyl)acetylene to a long-chain bifunctional bromoalkane followed by a second acetylide coupling to a short-chain iso bromoalkane, since higher yields are thus obtained. Spectral data is also presented for the first time for these two unusual fatty acids with potential as biomarkers and as topoisomerase I inhibitors.
Carballeira
Néstor M
NM
Department of Chemistry, University of Puerto Rico, PO Box 23346, San Juan, PR 00931-3346, USA. nmcarballeira@uprrp.edu
Montano
Nashbly
N
Padilla
Luis F
LF
D015415:Biomarkers / Q000737:chemistry; D004791:Enzyme Inhibitors / Q000138:chemical synthesis; D005229:Fatty Acids, Monounsaturated / Q000138:chemical synthesis*; D015394:Molecular Structure; D009227:Myristic Acids / Q000138:chemical synthesis*; D010169:Palmitic Acids / Q000138:chemical synthesis*; D013057:Spectrum Analysis; D013237:Stereoisomerism; D059004:Topoisomerase I Inhibitors; D014297:Trimethylsilyl Compounds / Q000737:chemistry
C518637:13-methyl-8-tetradecenoic acid; C518636:15-methyl-10-hexadecenoic acid; D015415:Biomarkers; D004791:Enzyme Inhibitors; D005229:Fatty Acids, Monounsaturated; D009227:Myristic Acids; D010169:Palmitic Acids; D059004:Topoisomerase I Inhibitors; D014297:Trimethylsilyl Compounds