17244-28-9

Synthesis of novel 4(3H)-quinazolinonyl aminopyrimidine derivatives has been achieved via quinazolinonyl enones which in turn were obtained from 2-acyl-4(3H)-quinazolinone. They have been assayed for biofilm inhibition against Gram-positive (methicillin-resistant Staphylococcus aureus (MRSA)) and Gram-negative bacteria (Acinetobacter baumannii). The analogues with 2,4,6-trimethoxy phenyl, 4-methylthio phenyl, and 3-bromo phenyl substituents (5h, 5j & 5k) have been shown to inhibit biofilm formation efficiently in MRSA with IC50 values of 20.7–22.4 μM). The analogues 5h and 5j have demonstrated low toxicity in human cells in vitro and can be investigated further as leads.

Herein, we report a mild, operationally simple method for Minisci C-H acetylation of N-heteroarenes using vinyl ethers as robust, inexpensive acetyl sources. The reactions do not require a conventional photocatalysis, electrocatalysis, metal catalysis, light activation, or high temperature. This method is thus significantly more sustainable than previously reported methods in terms of cost, reagent toxicity, and waste generation. This protocol can be expected to obtain medically relevant molecules from abundant feedstock materials.

The chalcone motif can be found in many molecules that contribute to essential biological processes, and many chalcone-containing compounds exhibit potent anti-cancer activity. Here, we synthesized two series of chalcone analogues (3a?s and 6a?s) based on substituting the chalcone B-ring or A-ring with a 4-oxoquinazolin-2-yl group, and then evaluated them for cytotoxic activity in human colorectal HCT-116 and breast cancer MCF-7 cell lines. Compounds 3a?s (in which a 4-oxoquinazolin-2-yl group functioned as the B-ring) were markedly more cytotoxic than compounds 6a?s (in which 4-oxoquinazolin-2-yl group functioned as the A-ring), based on their IC50 values to inhibit proliferation. Compound 3f was found as the most potent among 38 analogues and the mechanism of its cytotoxicity was investigated. Flow cytometry indicated that HCT-116 cells treated with compound 3f resulted in a dose-dependent accumulation of cells in the sub-G1 phase, which is representative of apoptotic cells. Subsequent assays (including Annexin V-FITC/PI, AO-EB, MitoSOX Red and JC-1 staining) confirmed that 3f exposure induced apoptosis in HCT-116 cells. Immunoblotting analysis indicated that cellular exposure to 3f increased the cleavage of PARP1 and caspases 3, 7, and 9. Taken together, this novel chalcone analogue has a cytotoxic effect on cultured cancer cell-lines that is likely mediated by inducing apoptosis via the mitochondrial death pathway.

The invention discloses a chalcone analogue containing a 4-oxygen generation quinazoline-2-radical as shown in the formula (I), wherein the definition of all substitute radicals can be found in description; besides, the invention further discloses a preparation method of the chalcone analogue. The chalcone analogue as shown in the formula (I) has an inhibition function on cell proliferation of human breast cancer (MFC-7) and human colon cancer (HCT-116) and can be used as anti-tumor medicine.

This paper presents reactions in which the putative cationic intermediate in the Morin rearrangement is trapped by aromatic carbon nucleophiles (indoles and furans). For example, reaction of sulfoxide 27 with trifluoroacetic acid in chloroform provides, among other products, indole 29 and indoline 30. The indoline was shown to be in equilibrium with the nine-membered ring bridged indole 31. Other examples of Morin rearrangement-trapping reactions are presented, and mechanisms for these transformations are proposed.

Syntheses of both enantiomers of chrysogine, 2-(α-hydroxyethyl)-4(3H)-quinazolinone, 1 from 2-ammobenzamide are reported. Thus reaction of 2-aminobenzamide and optically active α-acetoxypropionyl chloride gave 9, which upon saponification and cyclization induced by aqueous sodium carbonate at room temperature gave chrysogine. The enantiomeric purity of 1 was determined by NMR. Inversion of (-)-(S)-1, using the Mitsunobo reaction, gave (+)-(R)-1. Reduction of 2-acetyl-4(3H)-qumazolinone 2 with baker's yeast gave the S-enantiomer of 1. The cyclization method used could be extended and a number of 2-(a-hydroxy)alkyl-4-(3H)-quinazolinones are also reported.

The o.formylarylazomethylenetriphenylphosphoranes carrying an electron withdrawing group on the ylidic carbon undergo thermal intramolecular cyclization to 3-oxo-indazolin-2-yl-methylenephosphorane derivatives.The latter compounds, and their 1-alkyl derivatives, in turn, undergo thermal and/or acid catalyzed rearrangement to 4-oxo-1,4-dihydroquinazoline derivatives and PPh3.Some possible reaction mechanisms are discussed, and some synthetic applications of the above reactions are shown.