Band 21, Heft 3

Quinazoline derivatives have drawn attention in the field of heterocyclic chemistry because of their unique skeleton and interesting biological applications. This review summarizes the recent palladium-catalyzed reactions used to construct quinazoline and its related 4(3 H )-quinazolinone analogues. The mechanisms of some Pd-catalyzed reactions are also discussed.

The development of light-sensitive media based on organic, mostly heterocyclic compounds that have no fluorescence in their initial form but provide fluorescent photoproducts formation is considered in this review. Materials with photoinduced irreversible fluorescence appear to be the most promising in the design of recording media for 3D archive optical memory. Photoactivatable fluorophores are also of interest for use in cell biology.

This review summarizes the synthesis of quinolines and acridines by the reactions of anionically activated 2-(perfluoroalkyl)anilines. Mechanistic studies including isolation of the intermediate aza- ortho -xylylene are discussed.

Tricyclic indolizidines were synthesized in good yields from commercially available ethyl isocyanoacetate by a novel sequential alkylation, thiol-mediated radical cyclization, N -alkylation, and microwave-assisted Pauson-Khand reaction.

An efficient ligand- and catalyst-free intramolecular S -arylation leading to the direct synthesis of indalothiochromen-4-ones from simple dithioesters under mild conditions has been developed. This method is particularly noteworthy given its experimental simplicity, high generality, and good functional group toleration.

Optically active 4-substituted γ-lactones ( 3 and 4 ) were synthesized effectively using lipase-catalyzed optical resolution. N -methyl-4-hydroxyalkanamides ( rac - 1a – i ) as substrates were prepared from N -methylsuccinimide. The alkylation of N -methylsuccinimide using Grignard reagents generated from various alkyl halides followed by reduction resulted in N -methyl-4-hydroxyalkanamides. The optical resolution of rac - 1a – g was performed using Novozym 435-catalyzed stereoselective acetylation. The stereoselective preparation of 4-substituted γ-lactones ( 3 and 4 ) possessing various side chains such as isopentyl, phenyl, and phenethyl groups was achieved with more than 90% enantiopurity.

A one-pot synthesis of 4-alkyl-2-amino-4 H -chromene derivatives by base-initiated reactions of aliphatic aldehydes, malononitrile, and resorcinol in water is described.

A variety of heterocycles of synthetic and biological importance were prepared from 3-(indol-3-yl-methylene)-5-phenyl-2(3 H )-furanone ( 1 ) and its hydrazide 2 . Compounds 1 and 2 were used for the construction of pyridazin-3(4 H )-ones 4 and 6 ; 1,3,4-oxadiazoles 7 , 8 , and 10 ; and 1,2,4 - triazoles 12 , 14 , and 15 , all bearing a 3-indolyl moiety. The antimicrobial activities of the synthesized compounds were examined against six types of bacteria and two types of fungi.