Design, synthesis, and pharmacological characterization of some 2-substituted-3-phenyl-quinazolin-4(3H)-one derivatives as phosphodiesterase inhibitors.

Some 3-phenyl-quinazolin-4(3H)-one-2-thioethers (3a-e, 5a,b, 7a-e, 9a-d, 10a-d, and 12) along with 2-aminoquinazoline derivatives 13a-c were prepared and screened for their in vitro phosphodiesterase (PDE) inhibitory activity. Some compounds such as 7d,e, 9a,b,d, 10a,d, and 13b exhibited promising activity as compared with the non-selective PDE inhibitor IBMX. This inhibitory activity was validated by molecular docking in the active site of PDE7A and PDE4 to investigate their selectivity. Furthermore, the most active compound 10d (IC50 = 1.15 µM) was tested in vivo using behavioral tests. Compound 10d was able to pass the blood-brain barrier and improve scopolamine-induced cognitive deficits. Therefore, this core can be considered as a promising scaffold for further optimization to obtain new compounds with better PDE7A selective inhibition.

New ibuprofen derivatives as H2S and NO donors as safer anti-inflammatory agents.

Aim: Nonsteroidal anti-inflammatory drugs are expansively used worldwide. However, their prolonged administration is associated with serious side effects, especially gastrointestinal ulceration. Materials & methods: New ibuprofen derivatives hybridized with H2S- or NO-donating moieties were synthesized and evaluated for their anti-inflammatory activity and ulcerogenic effect. COX-1/COX-2 isozymes selectivity test for the most promising derivatives was performed. Molecular docking studies were performed. Results: Most of the compounds showed promising anti-inflammatory activity comparable to that of ibuprofen (% edema inhibition = 76.6 and ulcer index = 21.26) with much better gastrointestinal tract tolerance (ulcer indices ranging from 0 to 14.67), especially compound 2 -H2S donor- (% edema inhibition = 75.5 and ulcer index = 11.75) and compound 16 -NO donor- (% edema inhibition = 65.4 and ulcer index = 8.66).

Design, synthesis and SAR of new-di-substituted pyridopyrimidines as ATP-competitive dual PI3Kα/mTOR inhibitors.

PI3Kα/mTOR ATP-competitive inhibitors are considered as one of the promising molecularly targeted cancer therapeutics. Based on lead compound A from the literature, two similar series of 2-substituted-4-morpholino-pyrido[3,2-d]pyrimidine and pyrido[2,3-d]pyrimidine analogs were designed and synthesized as PI3Kα/mTOR dual inhibitors. Interestingly, most of the series gave excellent inhibition for both enzymes with IC50 values ranging from single to double digit nM. Unlike many PI3Kα/mTOR dual inhibitors, our compounds displayed selectivity for PI3Kα. Based on its potent enzyme inhibitory activity, selectivity for PI3Kα and good therapeutic index in 2D cell culture viability assays, compound 4h was chosen to be evaluated in 3D culture for its IC50 against MCF7 breast cancer cells as well as for docking studies with both enzymes.

Synthesis, anticonvulsant activity and molecular modeling study of some new hydrazinecarbothioamide, benzenesulfonohydrazide, and phenacylacetohydrazide analogues of 4(3H)-quinazolinone.

A new series of quinazoline analogues was designed and synthesized to get the target compounds 18-21, 30-41, 46-53, and 57-76. The Obtained compounds were evaluated for their anticonvulsant activity using PTZ and picrotoxin convulsive models. Compounds 47, 63, 68 and 73 proved to be the most active compounds in this study with a remarkable 100% protection against PTZ induced convulsions. Compounds 47, 63, 68 and 73 proved to be 10, 4, 4, and 5 fold more active, respectively than the used positive control sodium valproate. Structure activity correlation concluded valuable pharmacophoric information which confirmed by molecular modeling studies. Molecular docking study of 68 suggested its agonistic behavior toward GABAA receptor. The studied quinazoline analogues could be considered as useful templates for future development and further derivatization.

Synthesis, docking and biological activities of novel hybrids celecoxib and anthraquinone analogs as potent cytotoxic agents.

Herein, novel hybrid compounds of celecoxib and 2-aminoanthraquinone derivatives have been synthesized using condensation reactions of celecoxib with 2-aminoanthraquinone derivatives or 2-aminoanthraquinon with celecoxib derivatives. Celecoxib was reacted with different acid chlorides, 2-chloroethylisocyanate and bis (2-chloroethyl) amine hydrochloride. These intermediates were then reacted with 2-aminoanthraquinone. Also the same different acid chlorides and 2-chloroethylisocyanate were reacted with 2-aminoanthraquinone and the resulting intermediates were reacted with celecoxib to give isomers for the previous compounds. The antitumor activities against hepatic carcinoma tumor cell line (HEPG2) have been investigated in vitro, and all these compounds showed promising activities, especially compound 3c, 7, and 12. Flexible docking studies involving AutoDock 4.2 was investigated to identify the potential binding affinities and the mode of interaction of the hybrid compounds into two protein tyrosine kinases namely, SRC (Pp60v-src) and platelet-derived growth factor receptor, PDGFR (c-Kit). The compounds in this study have a preferential affinity for the c-Kit PDGFR PTK over the non-receptor tyrosine kinase SRC (Pp60v-src).

Synthesis and in vitro antiproliferative effect of novel quinoline-based potential anticancer agents.

Several derivatives with a quinoline scaffold and a flexible, semi-flexible or rigid side chains at position 8 of the quinoline ring were synthesized and assessed for their in vitro activity versus the human colon cancer cell line HT29 and the human breast cancer cell line MDA-MB231. The HT29 cell line was more refractory to the cytotoxic activity of some compounds, meanwhile all the quinoline derivatives except one displayed high to moderate activity against MDA-MB231 with IC50 values ranging between 4.6 and 48.2 µM. The most active derivative in this study against both tested cell lines was the Schiff's base 4e with IC50 of 4.7 and 4.6 µM against HT29 and MDA-MB231, respectively.

Synthesis of novel bis-anthraquinone derivatives and their biological evaluation as antitumor agents.

Cancer has become a major worldwide problem and drug resistance now is one of the most important problems in treatment of cancer. Anthraquinone derivatives represent one of the most important drugs that can be used in treatment of many types of cancer. In this study two series of novel bis-anthraquinone derivatives have been synthesized. Five of these compounds were chosen to be evaluated for their antitumor activity against human cancer cell lines by the National Cancer Institute (NCI, USA). Marked activity was shown for the tested compounds(2-6). The most active one was compound 6 with mean value -67.00 against all cell lines. Compounds 7 and 8 were found inactive.

Design, synthesis, biological evaluation, and comparative Cox1 and Cox2 docking of p-substituted benzylidenamino phenyl esters of ibuprofenic and mefenamic acids.

Nonsteroidal anti-inflammatory drugs (NSAIDs) are frequently associated with gastric mucosal and renal adverse reactions, related to inhibition of cyclooxygenase1 (Cox1) in tissues where prostaglandins exert physiological effects. This led us to develop a set of ibuprofenic acid and mefenamic acid esters, namely: 4-((4-substituted benzylidene)amino)phenyl 2-(4-isobutylphenyl)propanoate and 4-((4-substituted benzylidene)amino)phenyl 2-((2,4-dimethylphenyl)amino)benzoate analogs, which were synthesized by condensation of the corresponding acids with Schiff's bases [4-(4-substituted benzylideneamino)phenols] involving dicyclohexyl carbodiimmide (DCC) as mild dehydrating agent. The main objective is to reduce the GIT toxicity associated with acute and chronic NSAIDs use. Anti-inflammatory, analgesic as well as ulcerogenic activities of the prepared esters were evaluated in vivo and compared with that of ibuprofen as reference standard in all screenings, involving the carrageenan induced paw oedema model and hot plate method. Most of the synthesized esters showed remarkable analgesic and anti-inflammatory activities. Interestingly, all of the compounds were found to be non-ulcerogenic under the tested conditions. This evidence have suggested that modification of the carboxyl function of representative NSAIDs results in retained or enhanced anti-inflammatory and analgesic activities with reduced ulcerogenic potential. Additionally, a comparative AutoDock study into Cox 1 and Cox2 has been done involving both of rigid and flexible docking for potential selectivity of our compounds within different Cox enzymes and to find out the binding orientation of these novel esters into their binding site. Some of the newly prepared aforementioned compounds showed considerable more Cox2 over Cox1 binding affinities by flexible docking better than rigid one.

Synthesis of new 9-glycosyl-4,9-dihydropyrano [3,4-b]indole-1(3H)-ones as antibacterial agents.

A series of new 9-glycosyl-4,9-dihydropyrano[3,4-b]indole-1(3H)-ones 3 was synthesized in moderate to low yields. 4,9-Dihydropyrano[3,4-b]indole-1(3H)-ones (1) were coupled with different acetobromoglycopyranoses 2 in refluxing toluene in the presence of silver oxide to afford one coupling product of the respective N-glycosides. α-L-Arabinopyranosides 3j and 3m were the most active glycosides among the tested compounds against certain Gram positive and Gram negative bacterial strains.

Synthesis of 1H-indole-2,3-dione-3-thiosemicarbazone ribonucleosides as antibacterial agents.

A new isatin ribonucleoside (3) was synthesized in a good yield by trimethylsilyl trifluoromethanesulfonate (TMSOTf) catalyzed coupling reaction between the silylated nitrogenated base of 1H-Indole-2,3-dione (1) and 1,2,3,5-tetra-O-acetyl-beta-D-ribfuranose (2). Thiosemicarbazides 4a-e were utilized by the prepared ribonucleoside (3) to give new series of 1H-indole-2,3-dione-3-thiosemicarbazone ribonucleosides 5a-e. All compounds tested as antibacterial agents showed slight inhibitory activity against the selected bacterial strains.

Design and synthesis of novel benzopyran-2-one derivatives of expected antimicrobial activity through DNA gyrase-B inhibition.

In an attempt to find a new class of antibacterial agents, we have synthesized thirty new coumarin (2H-benzopyran-2-one) analogues. These derivatives include substituted azetidin-2-ones (beta-lactam) 3a-f, pyrrolidin-2-ones 4a-f, 2H-1,3,4-oxadiazoles 5a-f, and thiazolidin-4-ones 6a-f attached to 4-phenyl-2H-benzopyran-2-one through an oxyacetamido or an oxymethyl bridge. The target compounds were synthesized starting from 2-oxo-4-phenyl-2H-benzo[b]pyran-7-yl-oxyacetic acid hydrazides 2a-f. The new compounds were evaluated as DNA gyrase-B inhibitors through molecular modeling and docking techniques using the Molsoft ICM 3.4-8C program. The synthesized compounds were also screened for antibacterial activity against four different species of Gram-positive and Gram-negative bacteria; as well as screening against C. albicans for antifungal activity. The molecular modeling data were in accordance with the antimicrobial screening results.

Synthesis of novel 4-substituted-7-trifluoromethylquinoline derivatives with nitric oxide releasing properties and their evaluation as analgesic and anti-inflammatory agents.

Six derivatives of the general formula 2- or 4-(7-trifluoromethylquinolin-4-ylamino) benzoic acid N'-(nitrooxyacetyl or propionyl) hydrazide and an oxime of the formula 1-[4-(7-trifluoromethylquinolin-4-ylamino)phenyl]ethanone oxime were synthesized and tested for their in vivo anti-inflammatory, analgesic, and ulcerogenic properties, as well as their in vitro nitric oxide release ability. Compound 2-(7-trifluoromethylquinolin-4-ylamino)benzoic acid N'-(2-nitrooxy propionyl)hydrazide 12 showed an anti-inflammatory activity comparable to that of indomethacin in the carrageenan-induced rat paw edema test, and equipotency to glafenine in the acetic acid mice induced writhing model at 100mg/kg p.o., respectively. All the final compounds showed no tendency to induce stomach ulceration in rats; nitric oxide seems to contribute to their excellent safety profile.