Provided are a methane-production inhibitor capable of inhibiting methane production for a long period of time, and a method for inhibiting methane production using the composition. A methane-production inhibitor composition contains one or more compounds selected from compounds represented by formula [I] as an effective ingredient, and a method for inhibiting methane production uses the composition.

##STR00001##

(In formula [I], X represents an —OR.sub.1 group, a hydroxyl group, or a halogen atom, Y represents an —OR.sub.2 group or an —SO.sub.2R.sub.3 group, R.sub.1 represents a benzoyl group, R.sub.2 represents a methylsulfonyl group or a chloromethylsulfonyl group, and R.sub.3 represents a chloromethyl group or a hydroxymethyl group.)

Provided are a methane-production inhibitor capable of inhibiting methane production for a long period of time, and a method for inhibiting methane production using the composition. A methane-production inhibitor composition contains one or more compounds selected from compounds represented by formula [I] as an effective ingredient, and a method for inhibiting methane production uses the composition.

##STR00001##

(In formula [I], X represents an —OR.sub.1 group, a hydroxyl group, or a halogen atom, Y represents an —OR.sub.2 group or an —SO.sub.2R.sub.3 group, R.sub.1 represents a benzoyl group, R.sub.2 represents a methylsulfonyl group or a chloromethylsulfonyl group, and R.sub.3 represents a chloromethyl group or a hydroxymethyl group.)

Provided are a method for producing a terminal conjugated dienal compound without an oxidation reaction and a terminal hydroxyacetal compound useful as an intermediate in the method. More specifically, provided are a method for producing an (E)-dienal compound comprising the steps of: a metalation reaction of an alkynal acetal compound (1) to obtain an organic metal compound (2), an addition reaction of (2) to ethylene oxide to obtain a hydroxyalkynal acetal compound (3), a reduction reaction of (3) to obtain an (E)-hydroxyalkenal acetal compound (4), a functional group conversion reaction of (4) to obtain an (E)-alkenal acetal compound (5) having a leaving group X, an elimination reaction of (5) to obtain an (E)-dienal acetal compound (6), and a hydrolysis reaction of (6) to obtain the (E)-dienal compound (7); and others.

##STR00001##

Provided are a method for producing a terminal conjugated dienal compound without an oxidation reaction and a terminal hydroxyacetal compound useful as an intermediate in the method. More specifically, provided are a method for producing an (E)-dienal compound comprising the steps of: a metalation reaction of an alkynal acetal compound (1) to obtain an organic metal compound (2), an addition reaction of (2) to ethylene oxide to obtain a hydroxyalkynal acetal compound (3), a reduction reaction of (3) to obtain an (E)-hydroxyalkenal acetal compound (4), a functional group conversion reaction of (4) to obtain an (E)-alkenal acetal compound (5) having a leaving group X, an elimination reaction of (5) to obtain an (E)-dienal acetal compound (6), and a hydrolysis reaction of (6) to obtain the (E)-dienal compound (7); and others.

##STR00001##

A method for producing (2S,5S)/(2R,5R)-5-hydroxypiperidine-2-carboxylic acid represented by formula (10) below: ##STR00001##
the method including removing the protecting group from the hydroxyl group in a compound represented by formula (7) below: ##STR00002##
(wherein P represents a protecting group, R.sup.3 represents an alkyl group containing 1 to 4 carbon atoms, and A represents an alkyl group containing 1 to 10 carbon atoms, an aryl group containing 6 to 12 carbon atoms, an alkyloxy group containing 1 to 4 carbon atoms, or an aralkyloxy group containing 7 to 20 carbon atoms)
to synthesize a compound represented by formula (8) below: ##STR00003##
(wherein R.sup.3 represents an alkyl group containing 1 to 4 carbon atoms, and A represents an alkyl group containing 1 to 10 carbon atoms, an aryl group containing 6 to 12 carbon atoms, an alkyloxy group containing 1 to 4 carbon atoms, or an aralkyloxy group containing 7 to 20 carbon atoms).

A method for producing (2S,5S)/(2R,5R)-5-hydroxypiperidine-2-carboxylic acid represented by formula (10) below: ##STR00001##
the method including removing the protecting group from the hydroxyl group in a compound represented by formula (7) below: ##STR00002##
(wherein P represents a protecting group, R.sup.3 represents an alkyl group containing 1 to 4 carbon atoms, and A represents an alkyl group containing 1 to 10 carbon atoms, an aryl group containing 6 to 12 carbon atoms, an alkyloxy group containing 1 to 4 carbon atoms, or an aralkyloxy group containing 7 to 20 carbon atoms)
to synthesize a compound represented by formula (8) below: ##STR00003##
(wherein R.sup.3 represents an alkyl group containing 1 to 4 carbon atoms, and A represents an alkyl group containing 1 to 10 carbon atoms, an aryl group containing 6 to 12 carbon atoms, an alkyloxy group containing 1 to 4 carbon atoms, or an aralkyloxy group containing 7 to 20 carbon atoms).

The present invention relates a new process to synthesize 6-(7-((1-aminocyclo-propyl)-methoxy)-6-methoxyquinolin-4-yloxy)-N-methyl-1-naphthamide (AL3810) by deprotection of substituted benzyl 1-((6-methoxy-4-(5-(methylcarbamoyl)naphthalen-2-yloxy)quinolin-7-yloxy)-methyl)cyc-lopropylcarbamate (Formula I) under a diluted or weak acidic condition. A stable crystalline form of 6-(7-((1-aminocyclo-propyl)-methoxy)-6-methoxyquinolin-4-yloxy)-N-methyl-1-naphthamide has also been prepared. ##STR00001##

The present invention relates a new process to synthesize 6-(7-((1-aminocyclo-propyl)-methoxy)-6-methoxyquinolin-4-yloxy)-N-methyl-1-naphthamide (AL3810) by deprotection of substituted benzyl 1-((6-methoxy-4-(5-(methylcarbamoyl)naphthalen-2-yloxy)quinolin-7-yloxy)-methyl)cyc-lopropylcarbamate (Formula I) under a diluted or weak acidic condition. A stable crystalline form of 6-(7-((1-aminocyclo-propyl)-methoxy)-6-methoxyquinolin-4-yloxy)-N-methyl-1-naphthamide has also been prepared. ##STR00001##

Compounds of formula (I), wherein R.sub.1 is as defined in the claims, exhibit COMT enzyme inhibiting activity and are thus useful as COMT inhibitors. Methods of treatment and pharmaceutical dosage forms are also disclosed.

Compounds of formula (I), wherein R.sub.1 is as defined in the claims, exhibit COMT enzyme inhibiting activity and are thus useful as COMT inhibitors. Methods of treatment and pharmaceutical dosage forms are also disclosed.