Dimethoxymethane → 17,21-Diacetoxy-6-methylene-4-pregnene-3,20-dione

Reaction equation

[C:1]([O:4][C@:5]1([C@:29]2([CH3:30])[C@H:15]([C@H:16]3[C@H:26]([CH2:27][CH2:28]2)[C@:24]2([CH3:25])[C:19](=[CH:20][C:21](=[O:31])[CH2:22][CH2:23]2)[CH2:18][CH2:17]3)[CH2:14][CH2:13]1)[C:6](=[O:12])[CH2:7][O:8][C:9](=[O:11])[CH3:10])(=[O:3])[CH3:2].[CH3:32]OCOC.C([O-])(=O)C.[Na+].P(Br)(Br)(Br)=O>C(Cl)Cl>[C:1]([O:4][C@:5]1([C@:29]2([CH3:30])[C@H:15]([C@H:16]3[C@H:26]([CH2:27][CH2:28]2)[C@:24]2([CH3:25])[C:19](=[CH:20][C:21](=[O:31])[CH2:22][CH2:23]2)[C:18](=[CH2:32])[CH2:17]3)[CH2:14][CH2:13]1)[C:6](=[O:12])[CH2:7][O:8][C:9](=[O:11])[CH3:10])(=[O:3])[CH3:2]