reaction of dialkyl acetylenedicarboxylates 1a-c andpyrrole derivatives 2a-e in the presence of triphenylphosphite (tpp) was investigated and the effect of the pyrrole substitution was established. diastereoselectivity is observed with pyrroles, 2a,b, yieldingphosphonate ester derivatives 3a-f and 4,and their relative configuration is determined by 1h/13c and 31p nmr and confirmed by single x-r...

Intramolecular nucleophilic and electrophilic cyclization of N-alkyne-substituted pyrrole esters is described. Efficient routes towards the synthesis of pyrrolopyrazinone, pyrrolotriazinone and pyrrolooxazinone have been developed. First, N-alkyne-substituted pyrrole ester derivatives were synthesized. Introduction of various substituents into the alkyne functionality was accomplished by a copp...

Substituted pyrroles are an essential class of heterocyclic compounds. In this research, an efficient and eco-friendly method has been developed for the synthesis of pyrrole derivatives from the reaction of 2,5-hexanedione and primary amines. Magnetic nanoparticles supported on functionalized. 7-aminonaphthalene-1,3-disulfonic acid-functionalized. silica (Fe3O4@SiO2@Propyl–ANDSA) has been inves...

Other than triarylamines, which are protonated by strong acids both at their N-atom and aromatic rings, pyrrole its N-substituted derivatives were exclusively the carbon atoms of heteroaromatic rings. Whereas with trifluoromethane sulfonic acid (TFS) stable pyrrolium salts obtained, weaker trifluoroacetic (TFA) oligomers formed. E.g., from N-(tert-butyl)pyrrole a dimeric compound could be unamb...

A wide range of vinyl sulfone-modified carbohydrates have been prepared as starting materials for the synthesis of polysubstituted chiral pyrroles. All these vinyl sulfones reacted efficiently with ethylisocyanoacetate to generate a plethora of new pyrrole derivatives. Furanosyl rings opened up during pyrrole synthesis, and pyranosyl rings were opened up by reacting the pyrrole with POCl(3)/DMF...

The reaction at room temperature of an aldehyde with excess pyrrole in the absence of solvent affords the meso-substituted dipyrromethane. The reaction is catalyzed with trifluoroacetic acid or with BF9,0(Et)2. The dipyrromethaue is purified by crystallixation or by flash chromatography on silica with eluants containing 1% triethylamine. The reaction is compatible with aliphatic or aromatic ald...

Exogenous tryptophan is metabolized by Pseudomonas aureofaciens to yield pyrrolnitrin [3-chloro-4-(2'-nitro-3'-chlorophenyl)-pyrrole], an antifungal agent. The ability of this culture to metabolize tryptophan analogues in a similar manner was investigated by addition of the appropriate compound to the fermentation. Tryptophan precursors and metabolites or nonphenyl-substituted tryptophans had l...

The pyrrole derivatives la, b and 2a, b were used as precursors for the preparation of N-substituted pyrrole derivatives 3a, b-9a, b and pyrrolo[2,3-d]pyrimidines 13-16. Also, all the newly prepared products were tested for anti-inflammatory activity as analogues to fenamates, and some of them revealed moderate anti-inflammatory activity compared to the standard drug indomethacin.

An investigation of the reaction requirements to effect the Clauson-Kaas pyrrole synthesis led to the formulation of a new procedure that avoids the contact of pyrroles to heat or strongly acidic conditions that cause decomposition of the desired products. The procedure involves mild hydrolysis of 2,5-dimethoxytetrahydrofuran in water to the activated species 2,5-dihydroxytetrahydrofuran that r...

A series of substituted 2-phenacyl-3-phenyl-1H-pyrrole-4-carboxylates were prepared from substituted acetophenones in 6 steps. The final condensations between a chloroenal and an aminoketone were carried out under neutral conditions in parallel to yield the series listed below. Selected pyrrole derivatives proved to be potent hypolipidemic agents lowering serum triglyceride concentrations in CF...