First chemoenzymatic synthesis of immunomodulating macrolactam pimecrolimus

• Published in: Tetrahedron Letters
• Main Authors: P. Ferraboschi, D. Colombo, M. De Mieri, P. Grisenti
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2009
• Subjects: Ascomycin; Immunomodulator; Lipase; Macrolactam; Regioselectivity; Settore BIO/10 - Biochimica; Antarc*; Antarctica
• Online Access: http://hdl.handle.net/2434/66629; https://doi.org/10.1016/j.tetlet.2009.05.066

The preparation of pimecrolimus, a synthetic derivative of ascomycin endowed with immunomodulatory activity, requires the selective protection of 24-hydroxy group of the ascomycin, before elaboration of the 32 one. The aim was achieved by means of two regioselective Candida antarctica lipase-catalyzed steps. The structure of the new key intermediates, 24-, 32-monoacetates and 24,32-diacetate, was established by means of an unambiguous NMR study.