Abstract: The present invention relates to a process for preparing 9-deoxo-9(Z)-hydroxyiminoerythromycin A corresponding to formula (I) below: from 9-deoxo-9(E)-hydroxyiminoerythromycin A by reaction with a base in water or in a mixture of water/solvent of dialkyl ketone type capable of forming a crystallizable solvate with the desired 9(Z)-oxime; acidification of the reaction mixture to a pH of between 9 and 11; addition to the said mixture of an organic solvent; optionally concentration under vacuum of the resulting organic phase; and isolation of the desired 9(Z)-erythromycin oxime.

Abstract: The invention relates to a process for preparing compound of general formula I by reductive amination of the corresponding (4″)-carbonyl derivative, characterized in that it comprises: placing the said (4″)-carbonyl derivative in contact with at least one nitrogenous reagent and a Lewis acid under conditions that are favourable for converting the 4″ carbonyl function, reducing the resulting mixture using a reducing agent, and optionally deprotecting the hydroxyl function in position 2′, to give the expected compound of general formula I.

Abstract: The invention provides a process for the preparation of 9-deoxo-8a-aza-8a-homoerythromycin A and of its 8a-alkylated derivatives from 9-deoxo-9(Z)-hydroxyiminoerythromycin A via a stereospecific Beckmann rearrangement in a reaction mixture using pyridine as main solvent, resulting in imidate intermediates which are not isolated from said mixture and which are employed directly in a reduction stage using a sufficient amount of borohydride, after extraction of the pyridine with a hydrocarbon which is miscible with the latter and in which said imidates are insoluble. The compound V can be directly N-alkylated at the 8a-position using an aldehyde without being isolated from the reduction mixture.

Abstract: This invention is directed to methods for stereospecifically preparing [(1-optionally substituted aryl)- or (1-optionally substituted heteroaryl)]-2-substituted ethyl-2-amines, having chirality at the 2-position, and to intermediates to the substituted ethyl-2-amines.

Abstract: This invention is directed to a process for preparing N6-substituted adenosine derivatives, to intermediates useful therefor and to methods of preparing these intermediates.

Abstract: The present invention relates to a novel process for preparation of camptothecin and of its derivatives by convergent synthesis starting from a 3-(aminomethyl)quinoline derivative and 5-hydroxy-5-ethyl-6-oxo-5,6-dihydropyrancarboxylic acid and to the intermediates obtained.

Abstract: The subject-matter of the invention is a process for the stereoselective preparation of a compound of general formula I by stereoselective displacement by a nitrogenous nucleophilic compound of the activated alcohol functional group present at this 4″ position in a corresponding derivative of formula II.

Abstract: The invention relates to a process for preparing compound of general formula I 1

Abstract: The invention provides a process for the preparation of 9-deoxo-8a-aza-8a-homoerythromycin A 1

Abstract: The present invention relates to a process for preparing 9-deoxo-9(Z)-hydroxyiminoerythromycin A corresponding to formula (I) below: 1

Abstract: This invention is directed to methods for the preparation of [1S-[1a,2b,3b,4a(S*)]]-4-[7-[[-(3-chloro-2-thienyl)methyl]propyl]amino]-3 H-imidazo[4,5-b]pyridin-3-yl]]-N-ethyl-2,3-dihydroxycyclopentanecarboxamide, methods for the preparation of intermediates thereto, and to said intermediates themselves.

Abstract: This invention is directed to a process for preparing a pseudotetrapeptide of formula I or a salt or prodrug thereof wherein is optionally nitrogen protected azaheterocyclyl; is a single or double bond; q is 1-5; B is alkyl, cycloalkyl, cycloalkylalkyl, alkylcycloalkyl, alkylcycloalkylalkyl, aryl, aralkyl, alkylaryl, or alkylaralkyl; Q2 is H or a carboxylic acid protecting group; J is —H, alkyl, cycloalkyl, cycloalkylalkyl, alkylcycloalkyl, alkylcycloalkylalkyl, aryl, substituted aryl, aralkyl, substituted aralkyl; L is OR1, or NR1R2, where R1 and R2 are independently —H, alkyl, cycloalkyl, cycloalkylalkyl, alkylcycloalkyl, alkylcycloalkylalkyl, aryl, aralkyl, alkylaryl or alkylaralkyl; and p is 1 or 2 which comprises the coupling of two dipeptides or psuedopeptides.

Abstract: This invention is directed to methods for the preparation of [1S-[1a,2b,3b,4a(S*)]]-4-[7-[[1-(3-chloro-2-thienyl) methyl]propyl]amino]-3H-imidazo[4,5-b]pyridin-3-yl]-N-ethyl-2,3-dihydroxyc yclopentanecarboxamide, methods for the preparation of intermediates thereto, and to said intermediates themselves.

Abstract: This invention is directed to methods for stereospecifically preparing [(1-optionally substituted aryl)- or (1-optionally substituted heteroaryl)]-2-substituted ethyl-2-amines, having chirality at the 2-position, and to intermediates to the substituted ethyl-2-amines.

Abstract: The present invention relates to a novel process for preparing dialkoxy derivatives of the taxoid family by direct alkylation of the two positions 7 and 10 of deacetylbaccatin or derivatives thereof which are esterified in position 13.

Abstract: Novel derivatives of 1R- or 1S-2-azabicyclo?2.2.1!heptane with the general formula (I) or (I'), preparation and their application. ##STR1## In the general formulas (I) and (I'), R represents a hydrogen atom or a group with the formula ##STR2## respectively, in which R.sub.1 represents an alkyl group containing 1-4 carbon atoms and Ar represents an optionally substituted phenyl or a- or b-naphthyl group.

Abstract: A method for the preparation of a lactam compound of formula ##STR1## wherein R'.sub.1 and R".sub.1 independently are acyl or aroyl, or taken together form an optionally substituted methylene, and G.sub.1 is hydrogen or an amino protecting group, comprising oxidizing a bis O-protected 1R-2-azadihydroxybicyclo-?2.2.1!heptane compound of formula ##STR2## with about 0.1 mol % to about 1 mol % of RuO.sub.2 or hydrate thereof in the presence of about 3 equivalents of an oxidant to form the lactam compound with an enantiomeric excess of greater than or equal to about 95%.

Abstract: A method for the preparation of a compound of formula ##STR1## wherein R is hydrogen or, respectively, a group of formula ##STR2## R.sub.1 is alkyl; Ar is optionally substituted aryl; andR.sub.3' and R.sub.3" are hydrogen, alkyl or phenyl, or R.sub.3' and R.sub.3" taken together with the carbon atom to which they are attached form cycloalkyl, or salt thereof, comprising acid facilitated acetalizing or ketalizing of a compound of formula ##STR3## wherein R.sub.3' and R.sub.3" are as defined above, and R.sub.4' and R.sub.4" are alkoxy, or taken together with the carbon atom to which they are attached form carbonyl, with a compound of formula ##STR4## wherein * represents an R chirality;R, R.sub.1 and Ar are as defined above, or salt thereof in isopropanol.

Abstract: A compound of formula ##STR1## wherein R is a group of formula ##STR2## R.sub.1 is alkyl; and Ar is optionally substituted aryl.

Abstract: The subject-matter of the invention is a process for the stereoselective preparation of a compound of general formula I by stereoselective displacement by a nitrogenous nucleophilic compound of the activated alcohol functional group present at this 4? position in a corresponding derivative of formula II.