Abutiloside A, a 26-acylamino-3 beta, 16 alpha-dihydroxy-5 alpha-cholesta-22-one glycoside from Solanum abutiloides

In addition to solamargine and proto-dioscin, three new steroid glycosides, abutilosides A-C, have been isolated from roots of the Solanaceae Solanum abutiloides. The structure of abutiloside A has been elucidated as 3 beta, 16 alpha-dihydroxy-26-isovalerylamino-5 alpha,25 xi H-cholestan-22-one 3-O-[O-beta-D-xylopyranosyl-(1-->2)-O-alpha-L- rhamnopyranosyl-(1-->4)-beta-D-glucopyranoside]. De-N-acylation of its aglycone yielded solafloridine by 22,N-cyclization. Therefore, 26-aminocholestan-22-one derivatives are considered to be crucial intermediates in steroid biosynthesis. The co-occurrence of the (25R)-steroids soladulcidine, solafloridine and diosgenin together with abutiloside A in roots of S. abutilosides suggests that the configuration of abutiloside A at C-25 will also be R.