This invention discloses (20S)-1.alpha.-hydroxy-2.alpha.-methyl-19-nor-vitamin D.sub.3 and (20S)-1.alpha.-hydroxy-2.beta.-methyl-19-nor-vitamin D.sub.3 and pharmaceutical uses therefor. These compounds exhibit pronounced activity in arresting the proliferation of undifferentiated cells and inducing their differentiation to the monocyte thus evidencing use as an anti-cancer agent and for the treatment of skin diseases such as psoriasis as well as skin conditions such as wrinkles, slack skin, dry skin and insufficient sebum secretion. These compounds also have very significant calcemic activity and therefore may be used to treat immune disorders in humans as well as metabolic bone diseases such as osteoporosis.