Abstract:
A process for obtaining nitroxyalkylesters of the 2-(S)-(6-methoxy-2-naphthyl)-propanoic acid having an enantiomeric excess higher than or equal to 95 %, preferably higher than or equal to 98 %, characterized in that an halide of the 2-(S)-(6-methoxy-2-naphthyl)-propanoic acid of formula A-Hal, wherein A is the acid acyl residue, is reacted in an inert organic solvent with an aliphatic nitroxyalkanol HO-Y-ONO2, wherein Y is a C2-C20 alkylene or a cycloalkylene from 3 to 8 carbon atoms, or an alkylene as defined containing a cycloalkylene as defined, in the presence of an inorganic base.
Abstract:
A process for obtaining (nitroxymethyl)phenyl esters of salicylic acid derivatives of formula (I) wherein R1 is the OCOR3 group characterized in that it comprises the following steps: a) reaction of a halide of a salicylic acid derivative with hydroxybenzylalcohol in the presence of a base; b) nitration of the obtained product in anhydrous conditions by a mixture of nitric acid with a different inorganic acid, or an organic acid, or an anhydride of one or two organic acids; c) recovery of the final product.
Abstract:
A solid nitrating reagent comprises either a montmorillonite clay or a zeolite material incorporating an amount of gaseous dinitrogen pentoxide. The clay material can be type K10 and suitable zeolites include those designated ZSM-5, zeolite beta, zeolite F720 and zeolite F780 (all H form). The reagent is conveniently prepared by exposing a sample of the montmorillonite clay or zeolite material to gaseous dinitrogen pentoxide contained in a stream of ozonised oxygen at a sub-ambient temperature while agitating the clay or zeolite material. The temperature is in the range of -60 to -20 DEG C. In use the reagent is contacted with a substance to be nitrated in an inert solvent such as hexane or a perfluorocarbon at a temperature of -20 to 15 DEG C, preferably around 0 DEG C. Suitable substrates include alcohols, O-silyl ethers and silylamines.
Abstract:
Disclosed is a process for the synthesis of Nicorandil (1), 2-(nicotinamide)ethyl nitrate, starting from N-(2-hydroxyethyl)nicotinamide (15), using nitration with nitric acid in the presence of acetic anhydride Said synthesis method is particularly advantageous because it solves the safety problems involved in the use of nitric acid as nitrating agent, and allows a product with excellent yields and quality to be isolated.
Abstract:
A process for the continuous production of a compound of Formula (II), HO-R1-ONO2 (II) wherein R1 is a straight chain alkyl radical having from 3 to 6 carbon atoms, in a two-phase solvent system, comprising contacting a compound of Formula (I), HO-R1-OH (I) wherein R1 is as defined above, with nitric acid in the presence of a first solvent, wherein the compound of Formula (II) is continuously extracted into a second solvent, and the reaction is carried out in a mixing microreactor which provides a power loss of at least 1.3 times the power loss provided under identical conditions by a circular cross-section straight-channel microreactor having an internal diameter equal to the average hydraulic diameter of the mixing microreactor and a length equal to the length of the mixing microreactor.
Abstract:
A process for the preparation of compounds of formula: HO-A-ONO2 (I) wherein A is a C2-C6 alkylene chain by nitration of the corresponding alkanediols with 'stabilised' nitric acid is herein disclosed. The process is safer to operators and allows to obtain advantageous yields on an industrial scale.
Abstract:
The invention relates to a method for the production of liquid nitrate esters, e.g. nitro-glycerine, wherein an alcohol is esterified by means of nitrating acid and the reaction takes place in one or several microreactors.
Abstract:
The present invention relates to a new process for the preparation of NO-donating compounds using a sulfonated intermediate. The invention relates to new intermediates prepared therein suitable for large scale manufacturing of NO-donating compounds. The invention further relates to the use of the new intermediates for the manufacturing of pharmaceutically active NO-donating compounds.The invention further relates to a substantially crystalline form of NO-donating NSAIDs, especially 2-[2-(nitrooxy)ethoxy]ethyl {2-[(2,6-dichlorophenyl)amino]phenyl}acetate, the preparation thereof and to pharmaceutical formulations containing said crystalline form and to the use of said crystalline form in the preparation of a medicament.