CAS: 2322-77-2 EINECS: 219-034-4 MF: C20H28O2 MW: 300.44 Liquescens punctum:150-160ºC Assay: 90% min. Character: Album pulveris crystallini. Consuetudinem: 18-levonorgestrel,.Max LMG is a progestin derived steroid and not a 17-alpha alkylated steroid. Max LMG is structurally related to RU-486 and acts as an antiprogesterone, decreasing estrogen-like effects.