Synthesis of lanosterol analogs with modified side chains.
作者:YOSHIHIRO SATO、YOSHIKO SONODA
DOI:10.1248/cpb.29.356
日期:——
Starting from lanosteryl acetate (1b), we synthesized twelve lanosterol analogs (cf. Chart 1-3 ; 9, 11, 14, 16, 18a, 19, 26, 27a, 28, 29, 30, 32) with different sizes of side chain and 20-iso-24-dihydrolanosterol (37), for biological studies. The analogs have shorter side chains than 1b except for the 24-ethylidene derivative (19) and 37. 20-Iso-24-di-hydrolanosterol (37) was prepared via 20-iso-22-dehydro-24-dihydrolanosterol [obtained by the Wittig reaction of 20R, S-aldehyde mixture (6, 33) with isoamyl triphenylphosphonium iodide, followed by column chromatographic separation].
0021 – 4.0 μm), but not the normal WI‐38 cells. Furthermore, Western blot analysis suggested that 12 induces apoptosis by activation of caspases‐3, 8, and 9. These results will be useful for the synthesis of other tetracyclic triterpenoids or steroid N‐glycosides to increase their cytotoxicity and apoptosis‐inducing activities.
potent synthetic analogues of the naturally occurring triterpenoid lanosterol to reverse protein aggregation in cataracts. Lanosterol showed superiority to other scaffolds in terms of efficacy and generality in previous studies. Various modified lanosterol derivatives were synthesized via modification of the side chain, ring A, ring B, and ring C. Evaluation of these synthetic analogues draws a clear
HMG-CoA reductase (HMGCR) is the rate-limiting enzyme in the cholesterol biosynthetic pathway, and is the target of cholesterol-lowering drugs, statins. Previous studies have demonstrated that the enzyme activity is regulated by sterol-induced degradation in addition to transcriptional regulation through sterol-regulatory-element-binding proteins (SREBPs). While 25-hydroxycholesterol induces both HMGCR
Synthesis of lanosterol analogs with lengthened side chains and their effects on cholesterol biosynthesis from lanosterol.
作者:YOSHIHIRO SATO、YOSHIKO SONODA
DOI:10.1248/cpb.32.1912
日期:——
Starting from 3β-acetoxy-25, 26, 27-trinorlanost-8-en-24-al (1), eight lanosterol analogs (10-17) with longer side chains side chains than that of lanosterol were synthesized by Wittig reaction followed by catalytic hydrogenation. Cholesterol biosynthesis was examined in rat hepatic subcellular preparation (S10) incubated with [24-3H]-lanosterol in the presence of each of the eight lanosterol analogs. Some of the analogs (10 and 12) caused slight inhibition, but 16 and 17 showed no inhibitory effect. The structure-inhibitory activity relationship of lanosterol analogs on cholesterol biosynthesis from lanosterol is discussed.