ISOC procedure

As a result, diastereo- and enantiomerically pure functionalized nitro derivative (205) was synthesized in satisfactory yield. This compound was used in the ISOC procedure, which gave diastereo- and enantiomerically pure isoxazolidine (206) in good yield. The latter compound can be considered as a possible reagent for asymmetric synthesis. It should be noted that silylation in this procedure, like that described above (Scheme 3.145), was performed with the use of BSA as the silylating agent in the presence of a small amount of Hunig s base, the latter being evidently added for acceleration of silylation and stabilization of intermediate silyl nitronate. 

SENAs containing auxiliaries were successfully used in the ISOC procedure for the synthesis of enantiomerically pure polycyclic (96) (Scheme 3.146) and natural (210, 211) (Scheme 3.145) compounds. 

An expression to estimate ISOC using the intersection of the minimum oxygen concentration and the stoichiometric line is also found using a similar procedure. The analytical result is... 

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