Organic compounds -- part of the class 532-570 series – Organic compounds – Heterocyclic carbon compounds containing a hetero ring...
Reexamination Certificate
2011-01-18
2011-01-18
Krass, Frederick (Department: 1612)
Organic compounds -- part of the class 532-570 series
Organic compounds
Heterocyclic carbon compounds containing a hetero ring...
Reexamination Certificate
active
07872135
ABSTRACT:
A process for preparing 17β-substituted 4-azaandrost-1-en-3-one compounds of the general formula (I):or a pharmaceutically approved salt thereof,whereR is hydroxyl, optionally substituted, linear or branched (C1-C2)alkyl or (C1-C12)alkenyl; phenyl or benzyl; an —OR1radical, or an —NHR1radical, or an —NR1R2radical;R1is hydrogen, optionally substituted, linear or branched (C1-C12)alkyl or (C1-C12)alkenyl, or optionally substituted phenyl;R2is hydrogen, methyl, ethyl or propyl; or—NR1R2is a 5- or 6-membered heterocyclic ring,by (A) introducing protecting groups into the 3-keto-4-aza moiety of the corresponding 1,2-dihydro compound, so that a compound of the general formula (III) is formed:whereR3is trialkylsilyl or, together with R4, the —C(O)—C(O)— or —C(O)—Y—C(O)— radical;R4is alkyloxycarbonyl or phenyloxycarbonyl, preferably Boc (=tert-butyloxycarbonyl); or trialkylsilyl, or, together with R3, the —C(O)—C(O)— or —C(O)—Y—C(O)— radical;Y is —[C(R5)(R6)]n— or —CH(R5)═CH(R6)—, or ortho-phenylene;R5and R6are each independently hydrogen, linear or branched (C1-8)alkyl or alkenyl, optionally substituted phenyl or benzyl; andn is an integer of 1 to 4;and where, in the case that R is hydroxyl, it has optionally reacted with a protecting group;(B) reacting the resulting compound in the presence (i) of a dehydrogenation catalyst, and in the presence of (ii) optionally substituted benzoquinone, allyl methyl carbonate, allyl ethyl carbonate and/or allyl propyl carbonate, and(C) removing the protecting groups R3and R4and optionally converting the resulting compound to a salt.
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Müller Beat W
Schärer Norber
Webber Beat
Hoffmann & Baron , LLP
Krass Frederick
Milligan Adam
Siegfried Ltd.
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