1998 structure

structure (organic substances)K 9000

25 - 043Crystallographic Evidence of [1,5]Prototropic Shifts Occurring UponTransannular Diels–Alder Reaction of a 14-Membered MacrocycleLeading to a 5α-Steroid Skeleton. — During transannular Diels–Alderreaction of macrocycle (I) to yield adduct (II), which is further transformedinto 5α-steroid (III), two consecutive reversible prototropic shifts, the secondone is a [1.5]prototropic shift takes place, generating macrocycle (IV), thecrystal structure of which is confirmed by X-ray analysis. — (DROUIN,M.; COUTURIER, M.; DESLONGCHAMPS, P.; Acta Crystallogr., Sect. C:Cryst. Struct. Commun. 54 (1998) 2, 256-261; Dep. Chim., Fac. Sci., Univ.Sherbrooke, Sherbrooke, Que. J1K 2R1, Can.; EN)

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