A stereoselective total synthesis of the HCl salts of mycestericins F, G and ent-F
摘要:
The total synthesis of the HCl salts of two natural sphingolipid-related amino acid derivatives, mycestericins F 4 and G 5 together with unnatural ent-4 center dot HCl, starting from the four crucial scaffolds 6, 8, 9, 11 and utilizing the Wittig reaction to build the C-20 backbone, has been achieved. The selection of selective functional group interconversions accompanied with suitable protection-deprotection protocols in the coupling products 20 and 34 gave the desired structures. (C) 2012 Elsevier Ltd. All rights reserved.
An efficient synthesis of the polar part of sulfamisterin and its analogs
摘要:
An efficient synthesis of the polar part of sulfamisterin and its analogs starting from D-xylose is described. The corresponding allylic thiocyanates and trichloroacetimidates were subjected to aza-Claisen rearrangement that effectively generated a quaternary carbon having an amino group as one of the sub-stituents. Subsequent functional group interconversions afforded the highly functionalized branched aminopolyol 29 that is expected to have the crucial application in the construction of sulfamisterin. On the other hand, the second diastereoisomer 34 would be transformed to 2-epi-congener. With respect to the appropriate stereochemical arrangement, the prepared polar segments 29 and 34 can also be utilized for the synthesis of mycestericins (E, G) and their analogs. (C) 2012 Elsevier Ltd. All rights reserved.