Diastereoselective Synthesis of Saturated 14-Membered Ring γ-Hydroxy Macrolides

Abstract

Stereoselective synthesis of two diastereomers of a saturated 14-membered γ-hydroxy macrolide using conformational stereocontrol is reported.

Key words

macrocycles - lactones - macrolides - diastereoselectivity - conformational stereocontrol

References

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7

The diastereomeric ratio of the acetylated products was determined by GC.

9

The calculations of 4 should be considered as approximate because some of the force field (MM3*) parameters were low quality parameters. We did the calculations also in an MM2* force field but many of the obtained low energy conformations violated the Schweizer-Dunitz rule. [11]

12

Structural assignments of products 5 and 6 are based on the differences in the ¹H NMR shifts and coupling constants of the starting materials 7 and 9 [3] and on the X-ray structure of 9.