Trehazolin (2) is a specific inhibitor of trehalase, an enzyme that cleaves the reserve carbohydrates of many insects. We describe a short and efficient synthesis of trehazolin (2) and trehazolamine (5) that mimics its hypothetical biosynthesis. Starting molecule for the synthesis of trehazolamine (5) is glucose from which three chiral centers are conserved during the reaction sequence. The remaining two chiral centers of trehazolamine (5) are formed stereoselectively in a reductive cyclization of ketooxime ether 16 and the reduction of oxime ether 18. The overall yield of trehazolamine (5) is 22% over 8 steps from 15. The synthesis of trehazolin (2) from trehazolamine (5) follows a known procedure and is achieved in 63% over 3 steps.

The convergent synthesis of macrolide soraphen A 1 α is described starting from glucose (western part) and mannose (eastern part). Mannose was converted into a 2-deoxyribohexopyranoside that could be methylated and reduced stereoselectively. Chain elongation at CÐ6 was carried out by stereoselective addition of a magnesium acetylide. The two fragments (western and eastern) were assembled by a Julia olefination followed by macrolactonization. The introduction of the methyl group at CÐ2 of norsoraphen occurred stereoselectively for thermodynamic reasons.

From the simple building block D‐glucose, soraphen 1 a (R  CH3) and the derivative 1 b (R  H) have been prepared. Compound la is the parent compound of a new class of eighteen‐membered macrolides with interesting biological properties. One of the key steps of the total synthesis was the selective methylation of 1 b yielding 1 a.

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