Enantioselective synthesis of (R)-incrustoporin, an antibiotic isolated from Incrustoporia carneola

Synthesis of Heterocycles by Transition Metals-Catalyzed Cyclocarbonylation Reactions

“…Proton attack from X and metal elimination affords cyclic carbonyl compounds D [see refs. 24,28,33,39,72,89].…”

“…The enantio differentiation, which took place by using non-chiral conventional ligand could be attributed to the chiral starting material itself [71]. Pd2(dba)3 catalysed the cyclocarbonylation reaction of the highly enantiomerically enriched (R)-1-p-tolyl-1-pentyn-3-ol 95 leading to (R)-incrustoporin (R)-96 (Scheme 59), an important antibiotic isolated from Incrustoporia Carneola, with retention of configuration [72].…”

Synthesis of heterocycles by carbonylation of acetylenic compounds

“…85 This method was used for the synthesis of unnatural (S)-incrustoporin 172, the enantiomer of the antifungal antobiotic isolated from the basidiomycete Incrustoporia carneola (Scheme 70). 86,87 Ethynyl alcohols also produce 2(5H)furanones upon carbonylation using Pd(MeCN) 2 -(PPh 3 ) 2 (BF 4 ) 2 as catalyst. 88 A one-pot lactonisation of the alkynols 173 in the presence of the thio -thio or seleno -seleno organic compounds 174 and carbon monoxide occurred to furnish the substituted unsaturated lactones 175 in up to 70% yield (Scheme 71).…”

Synthesis of iminosugars via 1,3-dipolar cycloaddition reactions of nitrones to α,β-unsaturated sugar aldonolactones

“…Butenolides (unsaturated g-lactones) [38] can also be found as fragments of many natural products (Fig. 3) such as isocladospolide (21) [39], corrosolin, (22) [40] and (À)-incrustoporin (23) [41].…”