the procedure of example 3 was repeated using the appropriate starting materials the following compounds were obtained 4 amino n n bis 1 methylethyl 3 oxoandrost 4 ene 17 u03b2 carboxamide ir 1668 1634 cm 1 ms ci m z 415 100 m 1 ei m z 414 95 m 371 100 1 h nmr cdcl 3 0 80 s c 18 me 1 12 1 21 pr d 2 u00d7 i pr me 1 15 s c 19 me 1 38 1 41 pr d 2 u00d7 i pr me 2 8 3 3 2h br nh 2 3 38 1h hept i pr ch 4 19 1h hept i prch 13 c nmr cdcl 3 u03b4 121 83 132 16 132 64 136 23 171 63 194 29 20s 4 amino 3 oxopregn 4 ene 20 carboxylic acid methyl ester ir 3464 3370 1728 1666 1624 1586 1172 cm 1 ms ci m z 374 100 m 1 ei m z 373 70 m 330 100 1 h nmr cdcl 3 u03b4 0 73 3h s c 18 me 1 16 s c 19 me 1 19 d c 21 me 3 45 2h br nh 2 3 65 3h s ch 3 o 13 c nmr cdcl 3.