RESUMEN

Quinazolin-4-one, its heteroanalogues, and derivatives represent an outstandingly important class of compounds in modern organic, medicinal, and pharmaceutical chemistry, as these molecular structures are noted for their wide synthetic and pharmacological potential. In the last years, ever-increasing research attention has been paid to quinazolinone derivatives bearing alkenyl and alkynyl substituents on the pyrimidinone nucleus. The original structural combination of synthetically powerful endocyclic amidine (or amidine-related) and exocyclic unsaturated moieties provides a driving force for cyclizations, which offer an efficient toolkit to construct a variety of fused pyrimidine systems with saturated N- and N,S-heterocycles. In this connection, the present review article is mainly aimed at systematic coverage of the progress in using alkenyl(alkynyl)quinazolinones and their heteroanalogues as convenient bifunctional substrates for regioselective annulation of small- and medium-sized heterocyclic nuclei. Much attention is paid to elucidating the structural and electronic effects of reagents on the regio- and stereoselectivity of the cyclizations as well as to clarifying the relevant reaction mechanisms.

RESUMEN

When treated with the catalytic system Pd(OAc)2/PPh3/Cs2CO3/benzoquinone in dioxane or Pd(PPh3)2Cl2/t-BuONa/Cs2CO3/benzoquinone in toluene, 2-butenylquinazolin-4(3H)-ones undergo intramolecular aza-Wacker cyclization to give methylene-substituted pyrrolo(pyrido)[2,1-b]quinazolinones. The latter catalytic system is also efficient in the reaction of pentenyl(hexenyl)quinazolin-4(3H)-ones but, in these cases, the aminopalladation of C-H multiple bonds significantly competed with allylic C(sp3)-H bond activation which leads to hitherto unknown vinyl-substituted pyrrolo(pyrido)[2,1-b]quinazolinones.

RESUMEN

The synthesis of new N-(9,10-dioxo-9,10-dihydroanthracen-1(2)-yl)-2-(R-thio) acetamides was carried out using reaction of 2-chloro-N-(9,10-dioxo-9,10-dihydroanthracene-1(2)-yl)acetamides with functionalized thiols in the presence of potassium carbonate in N,N-dimethylformamide (DMF) at room temperature. Evaluation of the synthesized compounds on such indicators of radical scavenging activity as lipid peroxidation (LP) and oxidative modification of proteins (OMP) in vitro in rat liver homogenate was carried out. It was determined that the compounds with a substituent in the first position of anthracedione core showed better antioxidant properties than their isomers with a substituent in the second position. The compounds 6 and 7 with the best indicators of radical-scavenging activity were determined. Antioxidant effect in OMP processes was also determined for compound 10. The antiplatelet activity study in vitro revealed compound 10 with the inhibited effect of ADP-induced aggregation.

Asunto(s)

RESUMEN

A regioselective method for the synthesis of 1-(hydroxymethyl)-2,3-dihydropyrrolo[1,2-a]quinazolin-5(1H)-ones - close structural analogs of naturally occurring vasicinone alkaloids - is described. The procedure is based on PIFA-initiated oxidative 5-exo-trig cyclization of 2-(3-butenyl)quinazolin-4(3Н)-ones, in turn prepared by thermal cyclocondensation of the corresponding 2-(pent-4-enamido)benzamides. The products obtained have a good natural product likeness (NPL) score and therefore can be useful for the design of natural product-like compound libraries.

RESUMEN

A general approach to a new generation of spirocyclic molecules - oxa-spirocycles - was developed. The key synthetic step was iodocyclization. More than 150 oxa-spirocyclic compounds were prepared. Incorporation of an oxygen atom into the spirocyclic unit dramatically improved water solubility (by up to 40 times) and lowered lipophilicity. More potent oxa-spirocyclic analogues of antihypertensive drug terazosin were synthesized and studied in vivo.