1.

Synthesis of 4-(2-hydroxy-1-methyl-5-oxo-1H-imidazol-4(5H)-ylidene)-5-oxo-1-aryl-4,5-dihydro-1H-pyrrole-3-carboxylates, a new triazafulvalene system

(2E,3Z)-2-(1-methyl-2,5-dioxoimidazolidin-4-ylidene)-3-[(arylamino- or heteroarylamino)methylene]succinate 5 obtained by [2+2] cycloaddition of (5Z)-5-[(dimethylamino)methylene)]-3-methylimidazolidine-2,4-dione (1) and dimethyl acetylenedicarboxylate (2) followed by substitution with (hetero)aromatic amines, afforded by heating potassium salts. Acidification afforded mixtures of (E-)- and (Z)-isomers of 4,5-dihydro-1H-pyrrole-3-carboxylates, while alkylation produced the corresponding derivatives of a new triazafulvalene system.

COBISS.SI-ID: 34021893

2.

[2+2] Cycloaddition of electron-poor acetylenes to (E)-3-dimethylamino-1-heteroaryl-propenones: synthesis of highly functionalized butadienes

(2E,3Z)-2-(1-methyl-2,5-dioxoimidazolidin-4-ylidene)-3-[(arylamino- or heteroarylamino)methylene]succinate 5 obtained by [2+2] followed by substitution with (hetero)aromatic amines, afforded by cycloaddition of (5Z)-5-[(dimethylamino)methylene)]-3-methylimidazolidine-2,4-dione and dimethyl acetylenedicarboxylate acidification mixtures of (E-)- and (Z)-isomers of 4,5-dihydro-1H-pyrrole-3-carboxylates and by alkylation produced the corresponding derivatives of a new triazafulvalene system.

COBISS.SI-ID: 34086917

3.

Synthesis of 1,5,6,7-tetrahydro-4H-pyrazolo[4,3-c]pyridin-4-ones as conformationally constrained analogues of histamine

Theree synthetic methods for the preparation of 1,5-disubstituted 1,5,6,7-tetrahydro-4H-pyrazolo[4,3-c]pyridin-4-ones as heterocyclic histamine analogs were developed

COBISS.SI-ID: 34495237

4.

Synthesis of racemic, N-benzylated Neoechinulin A and Isoneoechinulin A*

Two N-benzylated analogues of antioxidant, radical scavenging and neuroprotective neoechinuline A alkaloid were prepared. Since stereochemistry, according to SAR studies, does not play an important role, both analogues were prepared in racemic form, using enaminone chemistry.

COBISS.SI-ID: 33976069

5.

TRANSFORMATIONS OF DIMETHYL (2E,3E)-2-[(DIMETHYL- AMINO)METHYLENE]-3-(1-METHYL-2,5-DIOXOIMIDAZOLIDIN-4- YLIDENE)SUCCINATE WITH C-NUCLEOPHILES

(2E,3E)-2-[(Dimethylamino)methylene]-3-(1-methyl-2,5-dioxoimi- dazolidin-4-ylidene)succinate was transformed with 1,3-dicarbonyl compounds via substituted dimethyl (2H-imidazol-4-yl)-2-butenedioates and dimethyl (2,5-dioxo-4-imidazolidinylidene)succinates 4a,b into 2H-pyrano[2,3-d]- pyrimidines cyclized by heating in glacial acetic acid into dimethyl 1H-pyrrolo[1,2-c]imidazole-6,7-dicarboxylate.

COBISS.SI-ID: 34691077