RESUMEN
A practical synthesis of a key intermediate for the proteasome inhibitor lactacystin from (R)-4-hydroxymethyl-2-phenyl-4,5-dihydrooxazol-4-ylmethyl acetate was established. (R)-4-Hydroxymethyl-2-phenyl-4,5-dihydrooxazol-4-ylmethyl acetate is a useful chiral building block for the synthesis of biologically active compounds containing alpha-substituted alpha-amino acid moieties.
Asunto(s)
Acetilcisteína/análogos & derivados , Inhibidores de Cisteína Proteinasa/síntesis química , Oxazoles/síntesis química , Acetilcisteína/síntesis química , Cromatografía Líquida de Alta Presión , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética , Solventes , Espectrometría de Masa por Ionización de Electrospray , Espectrofotometría InfrarrojaRESUMEN
Inhibition of secretory phospholipase A(2) (sPLA(2)) by cladocorans A and B and their diastereomers almost equaled that of manoalide.
Asunto(s)
4-Butirolactona/análogos & derivados , Antozoos/química , Inhibidores de Fosfodiesterasa , Fosfolipasas A/antagonistas & inhibidores , 4-Butirolactona/farmacología , Animales , Venenos de Abeja/enzimología , Abejas , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética , Fosfolipasas A2 , Estereoisomerismo , Terpenos/farmacologíaRESUMEN
Cladocorans A and B, isolated from the Mediterranean coral Cladocora cespitosa, are novel sesterterpenoids whose structures were initially proposed as 1 and 2, respectively. These designations, however, subsequently came under doubt. In the present study, the synthesis of compounds 5 and 6 was undertaken. The physical properties of 5 and 6 were found to be identical to those of natural cladocorans A and B, whose structures were thus concluded to be 5 and 6, respectively. Cladocoran B is thus clearly shown to be an olefinic regioisomer of dysidiolide and cladocoran A as its acetate.