NEW MATERIAL: 6-Fluoro-Δ1,4-3-keto steroids represented by formula I [wherein a broken line is a single (double) bond, R9 is H or F, R9-1 is H or forms epoxy between C9 and C11 together with one of R11-1 and R11-2, C11-1 and C11-2 are H or combined to form an = O group or either one of them is β-hydroxy or H and, when a double bond is present between C9 and C11, either one of them is H and the other one of them is absent. Formula II is a D-ring and a C17 side chain is formula III (R is methyl or ethyl)].

USE: An intermediate for producing 6α-fluoro-Δ1,4-3-keto steriods useful as a local anti-inflammatory agent.

PROCESS: For example, tertiary butoxide is added to tertiary butanol to use the resulting mixture as de-conjugation agent and a solvent and 6β-fluoro-Δ1,4-3- keto steroid represented by formula IV is de-conjugated and an ammonium chloride aq. soln. is used as a stop agent to stop reaction and steroid is isolated.