Process for the preparation of alkyl mercapto methyl ergoline derivatives
AssigneePoli Industria Chimica S.p A.
InventorsAlberto Mangia, Paride Grisenti
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Abstract
Process for the preparation of compounds active in the treatment of Parkinson's disease, and such compounds, having general formula (VI) wherein R4 may be, independently, a linear, branched or cyclic, saturated or unsaturated C1-8 alkyl radical, such as, for example, the radicals methyl, ethyl, propyl, butyl, isobutyl, tert-butyl, pentyl, cyclopentyl, hexyl, cyclohexyl and octyl. The process utilizes as starting materials the compound of formula (I) wherein R1 represents a linear, branched or cyclic, saturated or unsaturated C1-8 alkyl residue.
Claims29
A process for the preparation of a compound of formula VI,
- wherein R4 is a saturated or unsaturated C1-8 alkyl radical, comprising the following steps:
- a) reacting a compound of formula I
- wherein R1 represents a saturated or unsaturated C1-8 alkyl residue, with 3-halo-propionyl chloride or 2-halo-propionyl chloride in an aprotic organic solvent in the presence of a proton acceptor;
- b) reacting the compound or mixture of compounds obtained in step a) with calcium borohydride in tetrahydrofuran at a temperature of between 10 and 65° C.;
- c) reacting the compound obtained in step b) in an aprotic organic solvent with an alkylsulphonyl chloride in the presence of a proton acceptor;
- d) reacting the compound obtained in step c) in an aprotic organic solvent with a compound of formula R4SX, wherein R4 has the meaning given above and X is an alkali metal;
- and
- e) converting the compound obtained in step d) to compound VI by treatment with a reducing agent in an aprotic organic solvent.
A compound having the formula:
- wherein R2 and R3 are halogen and hydrogen, respectively, and R1 represents a saturated or unsaturated C1-8 alkyl residue.
A compound of formula III
A compound of formula IV
- wherein X is a halogen or a compound of the general formula R5SO3— and R5 is selected from methyl, ethyl, p-tolyl.
A compound of formula V
- wherein R4 is a saturated or unsaturated C1-8 alkyl residue.
Dependencies are inferred from the claim text.