Enzymatic desymmetrization of 2-amino-2-methyl-1,3-propanediol: asymmetric synthesis of (S)-N-Boc-N,O-isopropylidene-α-methylserinal and (4R)-methyl-4-[2-(thiophen-2-yl)ethyl]oxazolidin-2-one
摘要:
We report herein, the novel enzymatic desymmetrization of 2-tert-butoxycarbonylamino-2-methyl-1,3-propanediol 1. This method makes it possible to prepare (S)-N-Boc-N,O-isopropylidene-alpha-methylserinal 3, which is a chiral building block for the synthesis of a variety of a-substituted alanine derivatives. Moreover, optically active (4R)-methyl-4-[2-(thiophen-2-yl)ethyl]oxazolidin-2-one 4. one of the key intermediates in the synthesis of a novel immunosuppressant, has been prepared by this methodology. (c) 2005 Elsevier Ltd. All rights reserved.
We herein report the synthesis of a chiral phosphonium salt, [(4S)-4-methyl-2-oxo-1,3-oxazolidin-4-yl]methyl}(triphenyl)phosphonium iodide 13 to provide a new Wittig reagent for the general method of synthesizing α-substituted alaninol derivatives. Our method described here is widely applicable to reactions with various types of aldehyde to afford olefin products with high E-selectivity, enabling
We herein report an asymmetric synthesis of alpha,alpha-disubstituted alpha-amino alcohol derivatives 3, key intermediates of a novel immunomodulator, using enzymatic desymmetrization of 2-alkyl-2-tert-butoxycarbonylamino-1,3-propanediols 1a and 1b. This method makes it possible to prepare a chiral analogue of FTY720 4. These synthetic procedures allow for a broad structure variation in order to evaluate structure-activity relationships and the mechanism of action for sphingosine 1-phosphate-1 (SIP1) receptor agonist. (c) 2006 Elsevier Ltd. All rights reserved.