The invention provides a method for depolymerising a phenolic polymer, the method comprising reacting the phenolic polymer with dimethylsulphoxide (DMSO) and a hydrogen halide. The phenolic polymer may be selected from the group consisting of lignin and derivatives thereof. The hydrogen halide may be HBr. The quantity of hydrogen halide per gram of phenolic polymer may be from 30 mmoles to 70 mmoles. The quantity of DMSO per gram of phenolic polymer may be from 0.1 mole to 1 mole. The reaction may be performed at a temperature of from 100 to 120° C. The reaction may be carried out for between 10 h and 14 h. The product of the reaction may comprise vanillin.

The application relates to a process for the preparation of a compound of formula (II) by cyclisation of a polyene of formula (I), and to an intermediate of formula (III). The obtained compounds are useful intermediates in the preparation of specific isoprenoids, preferably in the production of vitamin A and derivatives of vitamin A.

##STR00001##

The application relates to a process for the preparation of a compound of formula (II) by cyclisation of a polyene of formula (I), and to an intermediate of formula (III). The obtained compounds are useful intermediates in the preparation of specific isoprenoids, preferably in the production of vitamin A and derivatives of vitamin A.

##STR00001##

The present invention is directed to inhibitors of tyrosinase, pharmaceutical compositions comprising such tyrosinase inhibitors, and methods of making and using the same. Specifically, included in the present invention are compositions of matter comprised of at least one 2,4-dihydroxybenzene analog, which inhibit the activity of tyrosinase and which inhibit the overproduction of melanin.

The present invention provides a process for preparing a (1,2-dimethyl-3-methylenecyclopentyl)acetate compound of the following general formula (3), wherein R represents a linear or branched alkyl group having 1 to 4 carbon atoms, the process comprising subjecting a haloacetaldehyde alkyl 2,3-dimethyl-2-cyclopentenyl acetal compound of the following general formula (1), wherein R is as defined above, and Y represents a halogen atom, to a dehydrohalogenation reaction in the presence of a base, followed by a rearrangement reaction to obtain a (1,2-dimethyl-2-cyclopentenyl)acetate compound of the following general formula (2), wherein R is as defined above, and subjecting the (1,2-dimethyl-2-cyclopentenyl)acetate compound (2) to an epoxidation reaction, followed by an isomerization reaction and then a methylenation reaction to obtain the (1,2-dimethyl-3-methylenecyclopentyl)acetate compound of the following general formula (3). The present invention also provides a process for preparing (1,2-dimethyl-3-methylenecyclopentyl)acetaldehyde of the following formula (4), the process comprising the aforesaid process for preparing the (1,2-dimethyl-3-methylenecyclopentyl)acetate compound (3), and converting an alkoxycarbonylmethyl group (i.e., —CH.sub.2C(═O)OR) of the (1,2-dimethyl-3-methylenecyclopentyl)acetate compound (3) to a formylmethyl group (i.e., —CH.sub.2CHO) to obtain (1,2-dimethyl-3-methylenecyclopentyl)acetaldehyde (4). ##STR00001##

The present invention provides a process for preparing a (1,2-dimethyl-3-methylenecyclopentyl)acetate compound of the following general formula (3), wherein R represents a linear or branched alkyl group having 1 to 4 carbon atoms, the process comprising subjecting a haloacetaldehyde alkyl 2,3-dimethyl-2-cyclopentenyl acetal compound of the following general formula (1), wherein R is as defined above, and Y represents a halogen atom, to a dehydrohalogenation reaction in the presence of a base, followed by a rearrangement reaction to obtain a (1,2-dimethyl-2-cyclopentenyl)acetate compound of the following general formula (2), wherein R is as defined above, and subjecting the (1,2-dimethyl-2-cyclopentenyl)acetate compound (2) to an epoxidation reaction, followed by an isomerization reaction and then a methylenation reaction to obtain the (1,2-dimethyl-3-methylenecyclopentyl)acetate compound of the following general formula (3). The present invention also provides a process for preparing (1,2-dimethyl-3-methylenecyclopentyl)acetaldehyde of the following formula (4), the process comprising the aforesaid process for preparing the (1,2-dimethyl-3-methylenecyclopentyl)acetate compound (3), and converting an alkoxycarbonylmethyl group (i.e., —CH.sub.2C(═O)OR) of the (1,2-dimethyl-3-methylenecyclopentyl)acetate compound (3) to a formylmethyl group (i.e., —CH.sub.2CHO) to obtain (1,2-dimethyl-3-methylenecyclopentyl)acetaldehyde (4). ##STR00001##

The present invention relates to deuterated 1-piperazino-3-phenyl-indanes and salts thereof with activity at dopamine receptors D.sub.1 and D.sub.2 as well as the 5HT.sub.2 receptors in the central nervous system, to medicaments comprising such compounds as active ingredients, to the use of such compounds in the treatment of diseases in the central nervous system, and to methods of treatment comprising administration of such compounds.

The present invention relates to deuterated 1-piperazino-3-phenyl-indanes and salts thereof with activity at dopamine receptors D.sub.1 and D.sub.2 as well as the 5HT.sub.2 receptors in the central nervous system, to medicaments comprising such compounds as active ingredients, to the use of such compounds in the treatment of diseases in the central nervous system, and to methods of treatment comprising administration of such compounds.

The present disclosure relates to methods and intermediates useful for preparing a compound of formula I. ##STR00001##
or a co-crystal, solvate, salt or combination thereof.

The present disclosure provides regioselective methods for synthesizing intermediates useful in making prostacyclin. The methods include heating the compound of Formula 2 at a temperature of 180° C. to 185° C. Wherein the heating ##STR00001##
comprises irradiating the compound of formula 2 with microwave radiation.