7alpha-hydroxypregn-4-en-3-one-20-carbaldehyde, process for producing the same, and process for producing 7alpha,21-dihydroxy-20-methylpregn-4-en-3-one from the same

摘要

7alpha-Hydroxypregn-4-en-3-one-20-carbaldehyde a process for producing the carbaldehyde and a process by which 7alpha,21-dihydroxy-20-methylpregn-4-en-3-one having a high purity, which is useful as an intermediate for medicines such as squalamine, can be efficiently produced from the carbaldehyde.