Solanum pseudoquina St. Hil was identified by Alfredo Paredes, and a voucher kept at Escuela Politecnica, Quito; trivial name, pululo. This was obtained from the Ecuadorian Andes, on the outskirts of Quito. In previous work, tests have been made for steroidal alkaloids [1]. In the present work green berries of this plant were crushed and extracted with MeOH. Chromatography of the alkaline CHCl3 extract yielded solaquidine (1) as colourless needles, mp 278-281°. The PMR spectrum showed the presence of two OMe groups, (δ 3.10 and 3.15), a most unusual feature in steroidal Solanum alkaloids. The MS showed a parent peak at m/e 444. Since an elementary analysis indicated the presence of only one N the true MW was established as 445 (C29H51NO2). The base peak at m/e 98 showed the presence of a Me piperidine side chain [2], and the two very abundant fragments at m/e 101 (60%) and m/e 127 (32 %) indicated that both OMe groups were located at C-3. It has been demonstrated that an ethylene ketal function at C-3 produces mainly fragments at m/e 99 and 125, if rings A and B of a steroid are not substituted [3]. Since solaquidine has two OMe groups at C-3 instead of an ethylene ketal, the fragmentation proceeds in a similar manner, but it produces fragments two a.m.u. greater, m/e 101 instead of 99, and m/e 127 in place of 125. The fact that both OMe groups are attached to the same carbon produces some shielding and explains why these protons appear at higher field than normally expected. The IR of the acetate (2) showed a strong N-acetyl band at 1630 cm-1 and a ketone band at 1710 cm-1. The PMR spectrum of 2 showed no OMe hands and only one N-acetyl group at 2.09. The shift of the angular C-19 Me resonance from δ 0.78 to 0.99 agreed with the presence of a ketone at C-3 [4]. The MS of 2 confirmed the absence of the two OMe groups since it showed an M+ at m/e 441 (C28H47NO2) and no fragments at either m/e 101 or 127. Based on these data a 3,3-dimethoxy-22β,25β-22,26-epimino-5α-cholestane structure (1) was assigned to solaquidine. The small amount of material isolated did not permit the determination of the absolute configuration at C-5, C-22, and C-25.