| abstract |
Provided is a novel vitamin D 3 derivative which is useful as a therapeutic agent for osteoporosis.nSpecifically provided is a vitamin D 3 derivative represented by formula (1) or a pharmaceutically acceptable solvate thereof.nIn the formula, R 1 represents a hydrogen atom, an alkyl group having 1-6 carbon atoms, an alkylcarbonyloxyalkyl group (wherein each alkyl has 1-6 carbon atoms) or an arylcarbonyloxyalkyl group (wherein the aryl has 6-10 carbon atoms and the alkyl has 1-6 carbon atoms); R 2 represents a hydrogen atom or an alkyl group having 1-6 carbon atoms, or alternatively R 2 may form, together with the other R 2 and carbon atoms bonded to the R 2 moieties, a cyclic alkyl group having 3-6 carbon atoms; R 3 represents an alkyl group having 1-6 carbon atoms, or alternatively R 3 may form, together with the other R 3 and carbon atoms bonded to the R 3 moieties, a cyclic alkyl group having 3-6 carbon atoms; X represents an oxygen atom or a methylene group; and n represents an integer of 1 or 2. |