A mixture of steroidal pyrimidine 3c (50 mg, 0.13 mmol) and potassium carbonate (200 mg, 1.44 mmol) in MeOH (8 mL) was refluxed for 3 h until the complete conversion of the starting material (TLC monitoring). The resulting mixture was cooled to room temperature and the solvent was removed under reduced pressure. The crude product was washed with water (6 mL) and dried to get colorless solid (42 mg, 95% yield). Rf 0.28 (CHCl3:MeOH, 5:0.1; visualized by UV light at 254 nm); m.p. 182–183°C. 1H NMR (600 MHz, DMSO-d6 + CCl4), δ: 0.92 (s, 3H, 18-CH3), 1.03 (s, 3H, 19-CH3), 0.99–1.09 (m, 2H, 1-CH2, 9-CH), 1.32–1.38 (m, 1H, 2-CH2), 1.48 (dt, J = 4.2, 12.6 Hz, 1H, 12-CH2), 1.50–1.55 (m, 1H, 14-CH), 1.58–1.73 (m, 4H, 2-CH2, 7-CH2, 11-CH2), 1.74–1.82 (m, 2H, 1-CH2, 8-CH), 2.04–2.19 (m, 4H, 4-CH2, 7-CH2, 12-CH2), 2.46 (dd, J = 14.4 Hz, 1H, 15-CH2), 2.55 (s, 3H, 2′-CH3), 2.72 (dd, J = 14.4 Hz, 1H, 15-CH2), 3.22–3.32 (m, 1H, 3-CH), 5.28–5.30 (m, 1H, 6-CH), 8.39 (s, 1H, H-4′) (the signal of OH group was not observed in the 1H NMR spectrum). 13C NMR (125 MHz, DMSO-d6 + CCl4), δ: 16.7 (18-CH3), 19.1 (19-CH3), 20.0 (11-CH2), 25.3 (2′-CH3), 27.4 (15-CH2), 30.2 (8-CH), 30.7 (7-CH2), 31.3 (2-CH2), 32.5 (12-CH2), 36.3 (10-C), 36.8 (1-CH2), 42.2 (4-CH2), 45.4 (13-C), 50.1 (9-CH), 55.2 (14-CH), 69.9 (3-CH), 119.8 (6-CH), 130.4 (16-C), 141.6 (5-C), 151.5 (4′-CH), 164.9 (2′-C), 180.7 (17-C). IR (KBr), cm−1: 3378 (OH), 2965, 2938, 2858, 2818 (CH), 1599, 1554 (C = C, C = N). HRMS (ESI) for C22H31N2O ([M+H]+): calcd 339.2431, found 339.2431.