Synthesis andin vitro evaluation of some novel benzofuran derivatives as potential anti-HIV-1, anticancer, and antimicrobial agents

A novel series of 1-(1-benzofuran-2-yl-ethylidene)-4-substituted thiosemicarbazides (2a-d) along with some derived ring systems: substituted-2,3-dihydro-thiazoles (3a-c, 4a-f) and thiazolidin-4-ones (5a-d and 6a-d), were synthesized. In addition, cyanoacetic acid-(1-benzofuran-2-yl-ethylidene) hydrazide (7) was used to prepare another new series of compounds consisting of substituted pyridin-2(1H)-ones (8a-c); 2-thioxo-2,3-dihydro-thiazoles (9a-d) and 2-thioxo-2,3-dihydro-6H-thiazolo[4,5-d]pyrimidin-7-ones (10a-c, 11a-c). The absolute configuration of compound 5c was determined by X-ray crystallography. The compounds prepared were evaluated for their in vitro anti-HIV, anticancer, antibacterial, and antifungal activities. Among the tested compounds, compounds 5c and 9a produced a significant reduction [symbols, see text] the viral cytopathic effect (93.19% and 59.55%) at concentrations > 2.0 x 10(-4) M and 2.5 x 10(-5) M respectively. Compound 9a was confirmed to have moderate anti-HIV activity. Compounds 2a, 2d, and 5c showed mild antifungal activity. However, none of the tested compounds showed any significant anticancer activity.     

Synthesis and biological evaluation of some 2,4,5-trisubstituted thiazole derivatives as potential antimicrobial and anticancer agents

We report on the synthesis and biological evaluation of two series of 2,4,5-polysubstituted thiazoles comprising the acid hydrazide functionality and some derived pharmacophores known to contribute to various chemotherapeutic activities. All newly synthesized compounds were subjected to in-vitro antibacterial and antifungal screening. Of the compounds tested, 13 derivatives displayed inhibitory effect on the growth of three Gram-positive strains while they lack activity against Gram-negative bacteria. Moreover, four compounds were able to exert antifungal activity against C. albicans. Potential antibacterial and antifungal activities were linked to the thiosemicarbazide function 6a-f and those substituted with both the thioureido and thiosemicarbazide moieties 12a-f. Compounds 6f and 12f (R = 4-F-C(6)H(4)) could be considered as the most active members in this investigation with a broad spectrum of antibacterial activity against three types of Gram-positive bacteria, together with an appreciable antifungal activity against C. albicans. Compounds 6d, 6f, and 12f were twice as active as ampicillin against B. subtilis. The best antifungal activity was shown by compound 6d 50% less active than clotrimazole. 17 compounds were selected and tested for their preliminary in-vitro anticancer activity according to the current one-dose protocol of the NCI. Three cell lines, non-small cell lung cancer Hop-92, ovarian cancer IGROV1, and melanoma SK-MEL-2, exhibited some sensitivity against most of the tested compounds. Compound 12f proved to be the most active anticancer member with a broad spectrum of activity against most of the tested subpanel tumor cell lines. Consequently, 12f was carried over to be tested in the five-dose assay.     

Synthesis of beta-hydroxypropanoic acid derivatives as potential anti-inflammatory, analgesic and antimicrobial agents

A series of new 3-(substituted) 3-hydroxy-propanoic acid ethyl esters 1a-c, hydrazides 2a-c, thiosemicarbazides 3a-f, and semicarbazides 3g, 3h has been synthesized. Cyclization of compounds 3a-d in basic medium yielded 1,2,4-triazole-5-thiones 4a-d. On the other hand, reaction of hydrazides 2a-c with CS(2 )in basic medium afforded 1,3,4-oxadiazole-5-thiones 5a-c. All the synthesized compounds were characterized by their physical and spectral analyses data. The newly synthesized compounds were evaluated for their anti-inflammatory, analgesic, and antimicrobial activities. Compounds 1c, 3g, 4a, 4b, 4c, and 5c exhibited comparable anti-inflammatory activity to that of indomethacin and compounds 1c, 4c, and 5c were more analgesics than acetyl salicylic acid. Compounds 4b, 4c, and 5c showed superior GI safety profile (33.3%, 33.3% and 50.0% ulceration) than that of indomethacin (100% ulceration) at 100 mg/kg oral dose. Compounds 4b, 4c, and 5c were also non-toxic with a median lethal dose (LD(50)) up to 200 mg/kg. The antibacterial and antifungal screenings identified compounds 3c, 4b, 4d, 5a, and 5b as the most effective against a variety of tested microorganisms.     

Synthesis and biological evaluation of some novel fused pyrazolopyrimidines as potential anticancer and antimicrobial agents

Synthesis and evaluation of anticancer and antimicrobial activity of some novel pyrazolopyrimidines and fused pyrazolopyrimidines are reported. Twelve analogs were selected to be evaluated for their in vitro anticancer potential against a panel of three human tumor cell lines: hepatocellular carcinoma HepG2, cervical carcinoma HelaS3 and colon carcinoma CaCo. The obtained data revealed that eight compounds namely; 6b, 6d, 7c, 8c, 10b, 12b, 13a and 13b were able to exhibit variable degrees of anticancer activities against the three used cell lines, of which compound 6d proved to be the most active. On the other hand, all the newly synthesized compounds were subjected to in vitro antibacterial and antifungal screening. Almost all the tested compounds were found to possess variable degrees of antimicrobial activities. Collectively, compounds 7c, 8c, 12b, 13a and 13b could be considered as possible agents with dual anticancer and antimicrobial activities.     

Synthesis and evaluation of some novel benzothiazole derivatives as potential anticancer and antimicrobial agents

Intensive efforts are underway worldwide to develop anticancer and antimicrobial agents. Therefore, a novel series of pyrido[2,1-b]benzo [d]thiazole and 2-(benzo [d] thiazol-2-ylamino)pyrimidine derivatives was synthesized. The synthesized compounds were evaluated for their anticancer activity. Among the tested compounds, compounds 3a, 3b, and 7 exhibited more cytotoxic action than the control drug doxorubicin (CAS 23214-92-8; IC50: 52 microg/ml). Compound 7 was the most potent cytotoxic, with an IC50 of 42.55 pg/ ml, while compounds 3a and 3b induced high cytotoxic action with IC50 values of 50.15 pg/ml and 50.45 pg/ml, respectively. Moreover, the synthesized compounds were screened for their antibacterial and antifungal activities. Compound 6 exhibited moderate antifungal activity against C. albicans with a minimum inhibitory concentration of 125 pg/ml.     

Synthesis of some novel D-glucuronic acid acetylated derivatives as potential anti-tumor agents

A structurally diverse series of Δ(4,5) -uronamide derivatives have been chemically synthesized starting from D-glucuronic acid itself by means of acetylation, activation, amide bond formation and base-catalyzed elimination protocols. Structure elucidation for all products along with optimization of the synthetic steps is described. The synthesized compounds were evaluated for their in-vitro anti-tumor activity against MCF-7, TK-10 and UACC-62 cell lines. The compounds 5, 11, 13, 15 and 16 were the most active against TK-10 cell line. On the other hand, the most active compounds against the MCF-7 cell line were 11 and 15. However, compounds 5, 7, 11, 13, 15 and 16 were the most active against the UACC-62 cell line.     

Design and synthesis of some substituted 1H-pyrazolyl-oxazolidines or 1H-pyrazolyl-thiazolidines as anti-inflammatory-antimicrobial agents

Four series of 1 H-pyrazole derivatives have been synthesized. The first series was synthesized starting with the reaction of 3-(5-bromo-2-thienyl)-1-phenyl-1 H-pyrazole-4-carboxaldehyde 1 with L-serine, L-cysteine, or L-penicillamine, followed by N-protection using (Boc)(2)O to provide compounds 2. The latter compounds could be N-deprotected by 4N HCl/dioxane to afford the second series 3 or reacted with NH(4)OH in the presence of DCC/HOBt to give the corresponding amides 4 followed by N-deprotection giving rise to compounds 5. The newly synthesized compounds were evaluated for their anti-inflammatory-antimicrobial activities. In addition, the ulcerogenic and acute toxicity profiles were determined. Compound 5b (2RS, 4R)-2-[3-(5-bromo-2-thienyl)-1-phenyl-1H-pyrazol-4-yl]-5-methylthiazolidine-4-carboxamide, proved to be the most active anti-inflammatory-antimicrobial agent in the present study with a good safety margin and no ulcerogenic effect.     

Synthesis and biological evaluation of some hydroxypyrazole derivatives as anti-inflammatory-antimicrobial agents

Some hydroxypyrazole derivatives 2-7 were synthesized by cyclocondensation of the keto-ester 1 with hydrazines hydrate or substituted hydrazines followed by reduction and acylation with acetic anhydride or trifluoroacetic anhydride. The newly synthesized compounds were evaluated for their anti-inflammatory, antimicrobial activities. In addition, the ulcerogenic and acute toxicity profiles were determined. Compounds N-(4-(5-hydroxy-1-trifluoroacetyl-1H-pyrazol-3-yl)phenyl) trifluoroacetamide 4b, 3-(4-nitrophenyl)-1-(4-methoxyphenyl)-1H-pyrazol-5-ol 5b, and N-(4-(5-hydroxy-1-methyl-1H-pyrazol-3-yl)phenyl)trifluoroacetamide 7b were proved to be the most active anti-inflammatory, antimicrobial agents in the present study with a good safety margin and minimal or no ulcerogenic effect.     

Synthesis, antimicrobial and anticancer activity of new thiosemicarbazone derivatives

Thiosemicarbazones of p-aminobenzoic acid (PABA) were synthesized and tested for their antimicrobial and anticancer activity. Hydroxamate derivatives 4a-4l were found to have better antimicrobial and anticancer activity than their acid counterpart. Compound 4d was found to have good antimicrobial activity against Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Vibrio cholerae, and Bacillus subtilis with IC(50) value of about 1 μM. Compound 4f showed potent antifungal activity against Candida albicans (IC(50) = 1.29 μM) and compound 4h showed potent anticancer activity (IC(50) = 0.07 μM).     

Synthesis of some quinoxaline derivatives containing indoline-2,3-dione or thiazolidinone residue as potential antimicrobial agents

The synthesis of some quinoxaline derivatives containing indoline-2,3-dione or thiazolidinone residue is described. The synthesized derivatives were screenedin vitro for their growth inhibitory activity against six species of bacteria, viz.Staphylococcus aureus, Streptococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Serratia marcescens andMycobacterium semegmatis. Most of the compounds exhibited antimicrobial activity especially those having indoline-2,3-dione moiety.     

Synthesis of some pyrazolines and pyrimidines derived from polymethoxy chalcones as anticancer and antimicrobial agents

The synthesis of a series of certain polymethoxy chalcones and some derived pyrazole, pyrimidine, and thiazolopyrimidine ring structures is reported. Eleven compounds 4 , 6 , 9 , 11 , 14–17 , 22 , 24 , and 25 were selected by the National Cancer Institute (NCI) to be screened for their in‐vitro anticancer activity, whereas all the synthesized compounds were evaluated for their in‐vitro antimicrobial activity. Compounds 4 , 6 , and 11 were found to possess a significant broad spectrum antitumor potential against most of the tested subpanel tumor cell lines. The pyrazolines 4 and 6 displayed remarkable growth inhibitory activities (GI₅₀ MG‐MID values of 2.10 and 1.38 µM, respectively), together with moderate cytostatic effects (TGI MG‐MID values of 47.9 and 42.7 µM, respectively). Meanwhile, the pyrimidin‐2‐one 11 showed a noticeable overall tumor growth inhibitory activity, together with high cytostatic and cytotoxic efficacies (GI₅₀, TGI and LC₅₀ MG‐MID values of 3.39, 17.4, and 61.7 µM, respectively). On the other hand, compounds 3 , 4 , 13 , 15 , 19 , 20 , and 23 were found to be the most active antimicrobial members in this investigation with a broad spectrum of activity. Compound 23 was four times superior to ampicillin against Pseudomonas aeruginosa. The best antifungal activity was demonstrated by compounds 4 , 5 , and 11 which possessed almost half the activity of clotrimazole against Candida albicans. Collectively, the obtained biological results suggest that compound 4 could be considered as a possible dual antimicrobial‐anticancer agent.     

Synthesis and study of some new N-substituted imide derivatives as potential anticancer agents

A new series of N-substituted imide derivatives have been synthesized by treating phthalic anhydride, naphthalic anhydride and their substituted derivatives with 2-hydrazino-1-imidazoline hydrobromide, various para-substituted aryl amines, aminoglutethimide and 2,4-dinitrophenyl hydrazine. Compounds 9, 10, 12, 18, 19, 23, 24 and 34-36 have been selected and screened for antineoplastic activity by National Cancer Institute, Bethesda, USA. Some newer aminoglutethimide derivatives 37-39 have also been prepared in order to study the effect of N-substitution on its pharmacological profile for the treatment of carcinoma. These compounds (37-39) have exhibited weak inhibition of human placental aromatase as compared to aminoglutethimide.     

Design and synthesis of 1-substituted-β-carboline derivatives as potential anticancer agents

In the present study, we designed and synthesized a series of 1-substituted-β-carboline derivatives through modification of position-1, 2 and 9 of β-carboline nucleus in order to discover novel leading compounds with better antitumor activities and less toxicity. Their structures were confirmed by ¹H NMR, ¹³C NMR, MS, IR and elemental analyses. All the target compounds were tested for cytotoxic activity against six cancer cell lines, including Bel-7402, HepG2, A549, A375, 786-0 and HT-29 by methyl thiazolyl tetrazolium (MTT) method. Studies of structure-activity relationships indicated that the effects of substituents in position-1 on cytotoxic activities were in an order as follows: 2-thienyl >2-chlorophenyl >4-chlorophenyl >benzyl group.     

Synthesis of some chalcones and pyrazolines carrying morpholinophenyl moiety as potential anti-inflammatory agents

Chalcones of 2a–f and their corresponding products, pyrazolines 3a–f , were synthesized and evaluated for their anti‐inflammatory activity against carrageenan edema in albino rats at a dose of 10 mg/kg. All the compounds of this series showed promising anti‐inflammatory activity. The most active compounds of this series, 2a , 2b , and 2d , were found to be most potent. They showed higher percentage of inhibition of edema than the standard drug indomethacin.     

Synthesis, anticancer, anti-HIV-1, and antimicrobial activity of some tricyclic triazino and triazolo[4,3-e]purine derivatives

In an effort to etablish new candidates with improved antineoplastic, anti-HIV-1 and antimicrobial activities, the synthesis of some new triazino and triazolo[4,3-e]purine derivatives is described: 6,8-dimethyl-1,4-dihydro-1,2,4-triazino[4,3-e]purine-7,9(6H, 8H)-diones 3–6; 5,7,9-trimethyl-1,2,4-triazolo[4,3-e]purine-6,8(5H, 7H, 9H)-diones 11–13, together with the synthesis of the 8-substituted purine derivative: 8-(3,5-diamino-1H-pyrazol-4-yl)diazenyl-1,3-dimethyl-1H-purine-2,6(3H, 7H)-dione 7. The prepared compounds were tested for their in vitro anticancer, anti-HIV and antimicrobial activities. The results of the in vitro anticancer screening revealed that compound 3 exhibited considerable activity against melanoma MALME-3?M, non-small lung cancer HOP-92 and breast cancer T-47D (GI₅₀ values of 25.2, 31.8, and 32.9?μM, respectively). The anti-HIV-1 results indicated that compounds 7 and 13c displayed moderate activity (maximum % cell protection 30.52 and 35.54 at 2?×?10^?4 M, respectively). The in vitro antimicrobial data showed that compound 12 was the most active against P. aeruginosa, it was equipotent to ampicillin (MIC?<?100?μg/ml). While compound 11d was the most active against P.?vulgaris, it was as active as ampicillin (MIC?<?50?μg/ml). In addition, compounds 12 and 13c were the most active against S. aureus (MIC?<50 and <25?μg/ml, respectively). On the other hand, the tested compounds devoid of antifungal activity except 6b and 11c which showed weak activity against A.?niger.     

Synthesis and antimicrobial activity of some pyridinyliminothiazoline derivatives

The synthesis of some pyridinyliminothiazoline derivatives starting from N-pyridine-N'-phenyl thiourea and alpha-halogenoacetophenones is described. The chemical structures of the compounds were elucidated. The prepared compounds were tested for antimicrobial activity.     

Novel pyrazole derivatives as potential promising anti-inflammatory antimicrobial agents

Four series of 1H-pyrazole derivatives have been synthesized. The first series was synthesized starting by condensing the hydrazine derivatives 1a-d with 4-(1-ethoxycarbonyl-2-oxopropyl)azobenzoic acid 2a in ethanol or glacial acetic acid to generate the corresponding pyrazoline derivatives 3a-d. Likewise, heating 1a-d with 4-(1-acetyl-2-oxopropyl)azobenzoic acid 2b gave rise to the pyrazole derivatives 4a-d. Similarly, reaction of 1a-d with ethyl 2-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-ylazo)-3-oxobutanoate 2c or 3-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl azo)pentane-2,4-dione 2d in ethanol or glacial acetic acid led to the corresponding pyrazoline derivatives 5a-d or pyrazole derivatives 6a-d. The newly synthesized compounds were evaluated for their anti-inflammatory-antimicrobial activities. In addition, the ulcerogenic and acute toxicity profiles were determined. Compound 6c, proved to be the most active anti-inflammatory-antimicrobial agent in the present study with a good safety margin and no ulcerogenic effect.     

Synthesis, antimicrobial evaluation, and docking studies of novel 4-substituted quinazoline derivatives as DNA-gyrase inhibitors

Quinazoline derivatives are reported to have anti‐inflammatory, analgesic, antibacterial, and anticancer activities. The incorporation of “OCH₂CONH₂” (oxymethylcarbamide) at 4^th position of the quinazoline ring was found to influence the biological activities of the molecules. With this rationale, some new oxadiazolyl methyloxy quinazolines, pyrazolyl acetoxy methyl quinazolines, triazolylmethyloxy quinazolines were synthesized from anthranilic acid through quinazolyl oxyacetylhydrazide intermediates. All the compounds were characterized by IR, ¹H‐NMR, EI‐MS, and C, H, N analyses and evaluated for their antimicrobial activity. Docking studies on the DNA‐gyrase enzyme (1KZN) show their role in the antimicrobial activity of the molecules and explain the higher potency of compounds 6a , 6b , 8a , 8b based on ReRanking scores and binding poses of the molecules.     

Synthesis of novel benzofuran and related benzimidazole derivatives for evaluation ofin vitro anti-HIV-1, anticancer and antimicrobial activities

Previously, we synthesized and evaluated several benzofuran derivatives containing heterocyclic ring substituents linked to the benzofuran nucleus at C-2 by a two- to four-atom spacer as potential anti-HIV-1, anticancer and antimicrobial agents. Among these derivatives, NSC 725612 and NSC 725716 exhibited interesting anti-HIV-1 activity. To further investigate the structure-activity relationship, we synthesized several new benzofuran derivatives derived from 2-acetylbenzofuran (2, 3a-c) and 2-bromoacetylbenzofuran (6; 7a,b; 8a,b). The compounds were designed to comprise the heterocyclic substituents directly linked to the benzofuran nucleus at C-2. Moreover, various related benzimidazoles derived from 2-acetylbenzimidazole and from 2-cyanomethylbenzimidazole (12a,b; 13a,b; 15; 16a,b) were also prepared as isosteres. The synthesized compounds were preliminarily evaluated for their in vitro anti-HIV-1, anticancer and antimicrobial activity. Compounds 2, 3a, 3b, and 12b showed weak anti-HIV-1 activity. Compound 6 exhibited mild activity against S. aureus, while compound 15 had mild activity towards S. aureus and C. albicans. However, no significant anticancer activity was observed with any of the tested compounds. From these results, we conclude that the presence of the spacer between the heterocyclic substituent and the benzofuran nucleus may be essential for the biological activity.     

Synthesis and biological evaluation of andrographolide derivatives as potent anti-HIV agents

In an attempt to develop potent anti-HIV drugs, 20 andrographolide derivatives were designed, synthesized, and evaluated for their in vitro anti-HIV activity. The screening results revealed that five compounds showed potent anti-HIV activities with therapeutic indices (TI) above 10. The most promising compound 6f shows a significant TI close to 34.07, with the potency to be a new lead.