Gino Del Ponte

Contribuições recentes da reação de hidroformilação na síntese de produtos farmacêuticos: parte II

The hydroformylation reaction represents one of the most important C1-chemistry area in the chemical industry. This catalytic process, which has been developed up to now mainly to the production of commodities chemicals, has shown a remarkable potential for the preparation of several categories of specialty chemicals and in particular pharmaceutical compounds. Arylpropanoic acids, various amines containing aryl groups, and intermediates for the preparation of vitamins, carbocyclic and heterocyclic compounds and many other classes of organic molecules endowed with pharmacological activity are currently accessible in good-to-high yields through hydroformylation of selected olefinic substrates. The asymmetric hydroformylation is going to reach the stage of maturity and hence to contribute in solving many troublesome synthetic problems connected with the preparation of pharmacologically active compounds with very high enantiomeric purity. The present survey emphasizes the usefulness of synthesis gas as a starting material in fine chemistry, which is expected to be important for industry.

Recent contributions of carbonylation reaction to the synthesis of fluorinated pharmaceutical compounds

Abstract Several organofluorine compounds endowed with unique pharmaceutical activity, such as fluorinated aminoacids, fluorinated arylpropanoic acids, etc. can be conveniently prepared by hydroformylation, hydrocarboxylation and hydroesterification of appropriated olefins containing one or more fluorine atoms in definite positions of the molecule. Many organic-fluorinated compounds obtained by carbonylation procedures represent very useful intermediates for the synthesis of pharmacologically active molecules, as for instance: fluor-indoles, fluor β-lactams and fluor uracils.

Optically active pheniramine by enantioselective hydrogenation of unsaturated amines, esters and acids using Ru(II)-complexes with B INAP as catalytic precursors

Pheniramine (3a) was prepared through enantioselective hydrogenation of various precursor compounds catalyzed by Ru(II)/BINAP complexes. In the case of N,N-dialkyl-3-phenyl-3-(2-pyridyl)allylamines (1 and 2) only the (Z)-isomer shows a satisfactory reactivity; moreover the chemoselectivity is affected by the hydrogenolysis of the alkylamino group of the substrate. The enantioselectivity did not exceed 50%. 3-Phenyl-3-(2-pyridyl)acrylic acids (9 and 10) and their ethyl esters (5 and 6) gave good chemical yields only at reaction temperature ⩾ 50°C; also in this case poor enantioselectivities (up to 35%) were achieved.

Preparation of (Z)-1-(3-nitrophenyl)-4-phenylbut-1-ene and (Z)-1-(3-nitrophenyl)-5-phenylpent-1-ene by Pd(0)-catalyzed cross-coupling reaction

The two nitroolefins, (Z)-1-(3-nitrophenyl)-4-phenylbut-1-ene and (Z)-1-(3-nitrophenyl)-5-phenylpent-1-ene, were stereospecifically prepared by Pd(0)-catalyzed cross-coupling reaction between (Z)-β-bromo-3-nitrostyrene and 2-phenylethyl- or 3-phenylpropyl zinc chloride, respectively. The yield reached 60% in spite of the well-known tendency of aralkyl organometallic halides to undergo β-elimination during the catalytic reaction. Only Pd-complexes displayed a satisfactory catalytic activity, the presence of the nitro group destroying that of related Ni-derivatives.

Synthesis of Some Functionalized Peptomers via Ugi Four-Component Reaction

Abstract This article describes the synthesis of new peptomers through a simple and efficient route using a one-pot Ugi four-component reaction. The synthesis started from either carboxylic acids or protected amino acids, primary amines, aldehydes, and isocyanides in anhydrous methanol and proceeded under stirring at room temperature. The reaction produced several functionalized peptomers in good yields (67–80%). These compounds are versatile multifunctional intermediates that can be further unprotected or functionalized to generate new molecules with numerous applications in the field of biomedicine. GRAPHICAL ABSTRACT

Síntese de sulfadiazina e sulfadiazina de prata em escala semi-micro: prática experimental em síntese de fármacos

The total synthesis of sulfadiazine and silver sulfadiazine from readily available starting materials was adapted to semi-micro laboratory scale and is proposed as an experiment in drug synthesis for undergraduate courses.