- New perspective for natural products synthesis: Concise synthesis of (+)-Sch 642305 by chiral auxiliary multiuse methodology
-
The synthesis of (+)-Sch 642305 is an example of chiral auxiliary multiuse methodology, which shows a new perspective for the synthesis of compounds with multiple asymmetric centers. Thus, (+)-Sch 642305 was concisely synthesized from the known compound.
- Fujioka, Hiromichi,Ohba, Yusuke,Nakahara, Kenji,Takatsuji, Mayuko,Murai, Kenichi,Ito, Motoki,Kita, Yasuyuki
-
p. 5605 - 5608
(2008/09/17)
-
- Concise asymmetric total synthesis of scyphostatin, a potent inhibitor of neutral sphingomyelinase
-
The concise asymmetric total synthesis of scyphostatin has been achieved by condensation of the optically active cyclohexane unit, prepared from the commercially available 1,4-cyclohexadiene by our own method, and the side chain, prepared by the method developed by Hoye and Tennakoon (T. R. Hoye, M. A. Tennakoon, Org. Lett. 2000, 2, 1481-1483). The modification of the epoxy cyclohexenone unit was achieved in a late stage of the total synthesis, and deprotection of the primary alcohol was conducted in the final step. During the synthesis several key reactions were attained: 1) intramolecular bromoetherification of the cyclohexadiene acetal; 2) stereoselective introduction of the tertiary alcohol, 3) deprotection of the acetal function to the aldehyde by combination with silyl triflate/2,4,6-collidine and the one-pot synthesis of the disilyl aldehyde compounds, with different types of silyl groups, from the dihydroxy acetal compounds; and 4) facile deprotection of the 2,4-dimethoxyphenylmethyl (2,4DMPM) protecting group of the primary alcohol.
- Fujioka, Hiromichi,Sawama, Yoshinari,Kotoku, Naoyuki,Ohnaka, Takuya,Okitsu, Takashi,Murata, Nobutaka,Kubo, Ozora,Li, Ruichuan,Kita, Yasuyuki
-
p. 10225 - 10238
(2008/09/18)
-