Abstract: New process for the synthesis of the antiinflammatory drug known as nabumetone that consists in reacting 2-acetyl-5-bromo-6-methoxynaphthalene with an alkyl acetate in presence of an alkaline alcoholate to get 4-(5-bromo-6-methoxy-2-naphthyl)-4-hydroxybut-3-en-2-one that by catalytic hydrogenation in a polar solvent and in presence of a base gives 4-(6-methoxy-2-naphthyl)butan-2-one known as nabumetone.

Abstract: A process for the preparation and purification of L-5-(2-hydroxypropionylamino)-2,4,6-triiodoisophthalic acid bis-(1,3-dihydroxypropylamide) by using ion-exchange resins is described.

Abstract: Naphthalenes of formula ##STR1## wherein X represents COCH.sub.3, COC.sub.2 H.sub.5, CH(CH.sub.3)COOH, CH(CH.sub.3)COOR, CH(CH.sub.3)CN and CH(CH.sub.3)CONHR.sub.1, R represents alkyl and R.sub.1 represents hydrogen, alkyl or hydroxyalkyl, are debrominated by means of acceptors of bromine, like alkylarenes and alkoxyarenes, in the presence of Lewis acids.

Abstract: New process for the synthesis of the .alpha.-(1-m.ethylethyl)-3,4-dimethoxyacetonitrile of formula (I): ##STR1## which is known as an intermediate in the synthesis of the drug internationally known as verapamil. The process starts from the isobutyryl-3,4-dimethoxybenzene of formula (II): ##STR2## which, by means of the Darzens condensation, gives an epoxyester which, by alkaline hydrolysis and subsequent decarboxylation, gives the .alpha.-(1-methylethyl)-3,4-dimethoxybenzeneacetaldehyde. This product is reacted with hydroxylamine to obtain the corresponding oxime that, by dehydration, gives the nitrile of formula I.

Abstract: New process for the synthesis of the N-methyl-3,4-dimetoxyphenylethylamine of formula ##STR1## intermediate in the synthesis of the drug internationally known as verapamil. The process starts from the 3,4-dimethoxybenzaldehyde which, by means of a Darzens condensation, gives an epoxyester that, by alkaline hydrolysis and subsequent decarboxylation, gives the 3,4-dimethoxyphenylacetaldehyde. This aldehyde gives the amine of formula I by reaction with monomethylamine followed by reduction with sodium borohydride.

Abstract: New process for the synthesis of optically active aminoacids of formula ##STR1## by treating compounds of formula ##STR2## which an optically active alcohol of formulaR.sub.4 --OH (III)d or 1To obtain a pair of diastereoiosmer esters of formula ##STR3## which is resolved in basic medium into the single diastereoisomer esters of formula ##STR4## from which the desired optically active aminoacid of formula (I) is obtained by treatment in acid medium.

Abstract: New process for the synthesis of the levodopa, L-(-)-2-amino-3-(3,4-dihydyphenyl)propionic acid, drug used in the treatment of the Parkinson's disease. The process consists in resolving with d-camphorsulfonic acid, or with a salt thereof, the d,l-2-amino-3-(3,4-dimethoxyphenyl)propionitrile, obtained from the 3,4-dimethoxyphenylacetaldehyde, and in the subsequent hydrolysis and demethylation, by means of concentrated solutions of haloid acids, of the d-2-amino-3-(3,4-dimethoxyphenyl)propionitrile and of salts thereof.

Abstract: A new process for the optical resolution of racemic mixtures of .alpha.-naphthylpropionic acids of formula ##STR1## wherein R.sub.1 is (C.sub.1-6) alkyl and R.sub.2 represents hydrogen or a halogen atom comprises reacting a racemic mixture of a compound of formula II ##STR2## wherein R.sub.1 and R.sub.2 have the above seen meanings and R.sub.3 is a reactive group, with an optically active aminoacid of formula ##STR3## wherein R.sub.4 represents a (C.sub.1-8) alkyl, phenyl, substituted phenyl, benzyl, substituted benzyl or carboxy, and m is an integer from 0 to 4, to give a pair of diastereoisomeric amides of formula ##STR4## wherein R.sub.1, R.sub.2, R.sub.4 and m have the above seen meanings, and M is a hydrogen atom or a cation of an alkali metal or a cation of an organic base. Compounds IV are resolved into the single diastereoisomeric amides d,d or 1,d, or d,1 or 1,1. Acid hydrolysis gives the optically active compound I.

Abstract: A new process for the optical resolution of racemic mixtures of .alpha.-naphthyl-propionic acids of formula ##STR1## This process comprises reacting a racemic mixture of a compound of formula ##STR2## with an optically active substance of formula R.sub.4 --NH.sub.2 (III), said substance being a .beta.-aminoalcohol, thus forming a pair of diastereoisomeric amides which are resolved into the single diastereoisomers by fractional crystallization. The obtained single diastereoisomeric amide is then hydrolyzed to give the desired optically active .alpha.-naphthyl-propionic acid of formula ##STR3## In the above compound I.fwdarw.III and VI, R.sub.1 is (C.sub.1-6)alkyl, R.sub.2 stands for hydrogen, halogen, mercapto, (C.sub.1-6)alkylthio, phenylthio, benzylthio, (C.sub.1-6)alkylsulfonyl, benzenesulfonyl, benzenesulfonyl substituted by halogen or (C.sub.1-4)alkyl, R.sub.3 is a reactive group and R.sub.4 is the residue of a primary or secondary alcohol.

Abstract: A process for the optical resolution of racemic mixtures of .alpha.-naphthyl-propionic acids of formula I ##STR1## which consists of reacting a racemic mixture of a compound of formula II ##STR2## with an optically active compound of formula IIIR.sub.4 --NH.sub.2wherein R.sub.4 is the residue of a primary or secondary alcohol which, taken with the NH.sub.2 radical, forms an optically active .beta.-aminoalcohol, to give a pair of diastereoisomeric amides, which is resolved into the single diastereoisomeric amides. Acid hydrolysis gives the optically active d or l .alpha.-naphthyl-propionic acids. The meaning of R.sub.1, R.sub.2, R.sub.3 is given.

Abstract: A new process for the synthesis of pyrido-imidazo-rifamycins of formula ##STR1## wherein R is hydrogen or acetyl, R.sub.1 and R.sub.2 independently represent hydrogen, (C.sub.1-4)-alkyl, benzyloxy, mono- or di-(C.sub.1-3)-alkylamino-(C.sub.1-4)-alkyl, (C.sub.1-3)-alkoxy-(C.sub.1-4)-alkyl, hydroxymethyl, hydroxy-(C.sub.2-4)-alkyl, cyano, halogen, nitro, mercapto, (C.sub.1-4)-alkylthio, phenylthio, carbamoyl, mono- or di-(C.sub.1-4)-alkyl-carbamoyl, or R.sub.1 and R.sub.2 taken together with two consecutive carbon atoms of the pyridine nucleus form a benzene ring optionally substituted by one or two methyl or ethyl groups.The process comprises reacting the rifamycin O of formula ##STR2## with a 2-aminopyridine of formula ##STR3## wherein R.sub.1 and R.sub.2 have the same meanings as before.

Abstract: A new process for the preparation of the d-2-(6-methoxy-2-naphthyl)-propionic acid of formula ##STR1## which comprises resolving a racemic mixture of the d- and 1-2-(5-halo-6-methoxy-2-naphthyl)-propionic acids of formula ##STR2## wherein halo stands for a halogen atom, recovering the d-isomer and subjecting this isomer to catalytic dehalogenation. Compound I is obtained in very high yields and with a high purity degree.

Abstract: A new process for the optical resolution of mixtures of d- and 1-2-(6-methoxy-2-naphthyl)-propionic acids, which comprises preparing a solution of a mixture of d-and 1-2-(6-methoxy-2-naphthyl)-propionic acids and an optically active organic base in a predetermined organic solvent, slowly cooling the obtained solution and seeding with crystals of a salt of d-2-(6-methoxy-2-naphthyl)-propionic acid with the optically active organic base containing a certain amount by weight of the organic solvent, and treating the obtained product with mineral acids in suitable organic solvents to obtain the free d-2-(6-methoxy-2-naphthyl)-propionic acid.