Synthesis and α-glucosidase inhibitory activity of chrysin,diosmetin, apigenin,and luteolin derivatives

Several derivatives have been synthesized from chrysin, diosmetin, apigenin, and luteolin, which were isolated from diverse natural plants. The α-glucosidase inhibitory activity of these compounds was evaluated. The glucosidase inhibitory activity of all derivatives （IC50 〈 24.396 μmol]L） was higher compared with that of the reference drug, acarbose （IC50=563.601 ±40.492μmol/L）, and 1- deoxynojirimycin （IC50 = 226.912± 12.573 μmol/L）. O3＇,O7-Hexyl diosmetin （IC50 = 2.406 ± 0.101μmol/L） was the most potent inhibitor identified. These compounds showed a higher inhibitory ability compared with their precursors except the luteolin derivatives. In general, the inhibitory activity of the synthetic derivatives was enhanced with long alkyl chains at positions 3＇, 4＇ and 7 of the flavonoid.     

Design,Synthesis and Antitumor Activity of Novel Indolin-2-one Derivatives Containing 4-Thiazolidinone Moiety

A series of novel indolin-2-one derivatives containing 4-thiazolidinone moiety(7a―7r) were synthesized and evaluated for their in vitro antitumour activities against MDA-MB-231(human breast cancer), H460(human lung cancer) and HT-29(human colon cancer) cell lines by standard 3-(4,5-dimethylthiazae-2-yl)-2,5-diphenyltetrazo- lium bromide(MTT) assay. Representative compounds(7d, 7k, 7m, 7p) with higher cytotoxicity were further examined against one normal cell line(WI-38, human fetal lung fibroblasts). The preliminary investigation shows that most of the compounds display moderate to excellent potency and high selectivity against different human cancer cell lines. In particular, the most potent compound 7m shows promising cytotoxicity against MDA-MB-231, H460 and HT-29 cell lines with IC₅₀ values of 0.78, 0.056 and 0.018 μmol/L, respectively. The potency is much higher than that of Sunitinib(IC₅₀=3.46 μmol/L against MDA-MB-231, IC₅₀=2.59 μmol/L against H460, IC₅₀=1.50 μmol/L against HT-29) by 4.4, 46.3 and 83.3 fold.     

Expeditious synthesis,antileishmanial and antioxidant activities of novel 3-substituted-4-hydroxycoumarin derivatives

A series of novel 3-substituted-4-hydroxycoumarin derivatives 6(a–1) were synthesized in high yield using one-pot three component coupling reaction catalyzed by ceric ammonium nitrate. These compounds were evaluated for antileishmanial activity against Leishmania donovani promastigotes and antioxidant activity(DPPH-radical scavenging activity). Two compounds, 6h(IC_(50)= 9.90 μmol/L) and 6i(IC_(50)= 6.90 μmol/L) displayed potent antileishmanial activity when compared with standard antileishmanial agents pentamidine(IC_(50)= 16.15 μmol/L) and miltefosine(IC_(50)= 12.50 μmol/L). Three compounds, 6c(IC_(50)= 10.79 μmol/L), 6h(IC50= 10.60 μmol/L), and 6i(IC_(50)= 10.73 μmol/L) showed significant antioxidant activity favorably with the antioxidant standards butylated hydroxy toluene(IC_(50)= 16.47 μmol/L) and ascorbic acid(IC_(50)= 12.69 μmol/L). A molecular docking study of compounds 6(a–1) suggested a possible mode of binding with the Adenine phosphoribosyltransferase enzyme of L.donovani. ADME properties were predicted in silico and support the potential of 6(a–1) to show favorable drug-like properties.     

Phenolic constituents from the roots of Alangium chinense

Three new phenolics(1–3) and twenty-eight known compounds(4–31) were isolated from an ethanolic extract of roots of Alangium chinense. Compound 11 exhibited antiviral activity against Coxsackie virus B3 with IC50 values of 16.89 mmol/L. Compounds 1, 10–17, 19–21, and 23 showed strong antioxidant activity against Fe~(2+)-cysteine-induced rat liver microsomal lipid peroxidation, with IC_(50) values of 0.14–8.18 mmol/L.     

Synthesis and pharmacological properties of naturally occurring prenylated and pyranochalcones as potent anti-inflammatory agents

An efficient approach has been developed for the synthesis of naturally occurring prenylated chalcones viz. kanzonol C(1), stipulin(2), crotaorixin(3), medicagenin(4), licoagrochalcone A(5) and abyssinone D(6) along with the pyranochalcones paratocarpin C(7), anthyllisone(8) and 3-O-methylabyssinone A(9).The key step of the synthesis is a Claisen–Schmidt condensation. Subsequently, their anti-inflammatory effects were investigated in lipopolysaccharides(LPSs)-induced RAW-264.7 macrophages. Of the synthesized chalcones, compounds 5(IC_(50)= 10.41 μmol/L), 6(IC_(50)= 9.65 μmol/L) and 8(IC_(50)= 15.34 μmol/L) show remarkable activity with no cytotoxicity. Compound 9(IC_(50)= 4.5 μmol/L)exhibits maximum(83.6%) nitric oxide(NO) inhibition, but shows slight cytotoxicity. The results reveal that the chalcones bearing the prenyl group at 3- and/or 5-position on ring A(acetophenone moiety), i.e.,1–4 and 7 show weak, or no inhibition activity, whereas chalcones having the prenyl group only on ring B(aldehyde part), i.e., 5, 6 and 8 show significant activity on the production of inflammatory mediated NO with no cytotoxicity.     

Synthesis of Aminoalkyl-substituted Polymethoxychalcone Derivatives and Their Antiproliferative Activities Against Three Human Cancer Cell Lines

Two novel series of sixteen aminoalkyl-substituted polymethoxychalcone derivatives 2a-2h and 3a-3h were synthesized from 2'-hydroxy-3,4,5,4',6'-pentamethoxy chalcone(1) through extending alkoxy side chain at the 2'-position, and introducing amine hydrogen bond receptor at the end of the side chain. The structures of all the synthesized compounds were confirmed by ¹H NMR, ¹³C NMR and MS techniques. Furthermore, all the compounds were tested for antiproliferative activities in vitro against a panel of three human cell lines(HeLa, HCC1954 and SK-OV-3) via CCK-8 assay. The results show that all the target compounds exhibit antiproliferative activities against the three human cancer cells with IC₅₀ values of 4.62-48.21 μmol/L, except compound 2h against SK-OV-3 cells. Most of these compounds were more active when compared to the positive control cis-Platin.     

6,7-seco-ent-Kaurane diterpenoids from lsodon sculponeatus and their bioactivity

One new 6,7-seco-enr-kaurane diterpenoid,sculponin T(1),was isolated from the aerial parts of Isodon sculponeatus,along with four known analogs,sculponeatin J(2),sculponeatin K(3),sculponeatin C(4),and sculponeatin Q(5).Their structures were elucidated by extensive spectroscopic analysis and by comparison with data reported in the literature.Significant cytotoxic activity was observed for compound 2 against five human tumor cell lines with IC_(50) values ranging from 1.8 μmol/L to 3.3 μmol/L,and it also inhibited NO production in LPS-stimulated RAW264.7 cells,with IC_(50) value of 3.3 μmol/L.     

Periconones B-E,new meroterpenoids from endophytic fungus Periconia sp.

Periconones B-E(1-4),four new polyketide-terpenoid hybrid molecules were isolated from the endophytic fungus Periconia sp.F-31.Their structures and absolute configurations were established by extensive spectroscopic data analysis and electronic circular dichroism(ECD).Compound 4 exhibited in vitro cytotoxic activity against the human MCF-7 tumor cell line with an IC_(50) value of 4.2 μmol/L,and compound 1 displayed anti-HIV activity with an IC_(50) value of 18.0 μmol/L.     

Synthesis and in vitro cytotoxic activities of sorafenib derivatives

A series of novel sorafenib derivatives have been designed and synthesized.The cytotoxic activities of these compounds were tested in three tumor cell lines.Most of the compounds showed potent antiproliferative activity against the tested cell lines with IC50= 0–20 mmol/L.Some compounds demonstrated competitive antiproliferative activities to sorafenib against all three cancer cell lines.Among them,compound 5g demonstrated significant inhibitory activity against A549,ACHN and MDAMB-231 cell lines with IC50values of 1.29,1.99,3.11 mmol/L,respectively.     

Development of bis-thiobarbiturates as successful urease inhibitors and their molecular modeling studies

Bis-thiobarbiturate derivatives 1–15 have been synthesized, characterized by1 HNMR and EI-MS and screened for urease inhibition. All compounds showed various degree of urease inhibitory activity with IC_(50) values ranging 7.45 0.12 74.24 0.81 mmol/L while the standard thiourea behaved normally(IC_(50) = 21.10 0.12). Compounds 1(IC_(50) = 7.45 0.12 μmol/L), 9(IC_(50) = 18.17 1.03 μmol/L) and 13(IC_(50) = 8.61 0.45 μmol/L) showed excellent urease inhibitory activity in the series. Molecular modeling studies were performed to understand the binding site with the bimetallic nickel center of the enzyme.Structure-activity relationship has also been established for these compounds. This study identified bisthiobarbiturate as a novel class of urease inhibitors.     

Synthesis and Tumor Cytotoxicity of Novel 1, 2, 3-Triazole-substituted 3-Oxo-oleanolic Acid Derivatives

Fifteen novel 3-oxo-oleanolic acid esters bearing aryl substituted 1,2,3-triazolyl methyl moiety were synthesized via the method of Copper(I)-catalyzed Huisgen cycloaddition. The cytotoxicity evaluation results of these compounds against five human tumor cell lines show that most of these compounds presented potent activity and selectivity against A375-S2 and HT1080 cells. Compound 6c, with a p-NO₂ at the bezene ring, possesses the best inhibitory activity against A375-S2(IC₅₀=2.82 μmol/L) and HT1080(IC₅₀=1.69 μmol/L).     

Syntheses and Anti-cancer Activities of Derivatives of Tetrandrine and Fangchinoline

A series of derivatives of tetrandrine and fangchinoline was designed and synthesized to find more active anti-cancer compounds. Their anti-cancer activities were tested against human hcpatocellular carcinoma BEL-7402 and PLC/PRF/5 cells, human lung adenocarcinoma A549 cells as well as human leukaemia K562 cells, and the structure-activity relationship（SAR） was also studied. All the compounds except BI exhibited superior inhibitory ac- tivities against PLC/PRF/5 cells with half maximal inhibitory conccntration（ICs0） values of less than 15 μmol/L, and compounds A2, A4, B2 and B4 showed IC50 values of less than 9 pmol/L. Compounds A2, A6, B2 and B4 showed potent anti-cancer activities against all the tested cells with 1C5o values of less than 10 pmol/L. The results show that terandrine and fangchinoline derivatives are potential suppressors to human cancer.     

Design,Synthesis and Activities of Aziridine Derivatives of N5-Methyltetrahydrofolate Against Methionine Synthase

Aziridine derivatives of N⁵-methyltetrahydrofolate were designed and synthesized based on the mechanism of methionine synthase, and their biological activities were investigated as well. The aziridine derivatives 1 and 6 exhibited superior inhibitory activities(IC₅₀: 5.05 and 4.15 μmol/L, respectively) compared to the corresponding chain analogue 4(IC₅₀=24.42 μmol/L). The results suggest that the aziridine derivatives can get potential activities against nucleophilic methionine synthase.     

Identification of hydrazone moiety-bearing aminopyrimidines as potent antitumor agents with selective inhibition of gefitinib-resistant H1975 cancer cells

Based on our previous work,a series of hydrazone moiety-bearing aminopyrimidines were synthesized.The compounds were evaluated for inhibitory activities against EGFRT790M/L858 R and antiproliferative activities against H1975 and A549 NSCLC cell lines harboring different forms of EGFR.Compounds 7f and7 k exhibited potent and selective activity in inhibition of gefitinib-resistant H1975 cancer cells(IC_(50);0.45,0.2μmol/L) while were much less active on A549 cancer cells(IC_(50);52.83,100μmol/L).Both compounds could be served as promising lead compounds for further investigation.     

Alkaloids from the endophytic fungus Penicillium brefeldianum and their cytotoxic activities

One new indoloditerpene,6,7-dehydropaxilline(1),one new indole-diketopiperazine,spirotryprostatin F(2),and one new 13-membered macrolide,N-demethylmelearoride A(3),as well as 8 known alkaloids(4-11),were isolated from the solid cultures of the endophytic fungus,Penicillium brefeidianum.The structures and absolute configurations of compounds 1-3 were elucidated by comprehensive spectroscopic analysis and the circular dichroism(CD) exciton chirality method.All the metablites were evaluated for their cytotoxic activites against three human tumor cell lines.Compound 2 exhibited cytotoxicities against HepG2 and MDA-MB-231 cells with IC_(50) values of 14.1 μmol/L and 35.5μmol/L,respectively.Compound 3 showed moderate activity against HepG2 cells with IC_(50) values of 36.6 μmol/L.     

Synthesis and biological evaluation of 3-(piperidin-4-yl)isoxazolo[4,5-d]pyrimidine derivatives as novel PI3Kδ inhibitors

An efficient synthesis of novel 3-(piperidin-4-yl)isoxazolo[4, 5-d]pyrimidine scaffold has been designed and deveopled. A series of 5-phenylurea derivatives was synthesized using this method. Their cytotoxic activities against breast cancer cell line BT-474 were evaluated by CCK-8 assay. Most of them showed potent anti-proliferative activities, of which compound 20 and 21 exhibited IC₅₀s of 1.565 μmol/L and 1.311 μmol/L, respectively. Furthermore, compound 20 and 21 also showed potent inhibitory activities against PI3Kδ with IC₅₀s of 0.286 μmol/L and 0.452 μmol/L, respectively. These results indicate that these 3-(piperidin-4-yl)isoxazolo[4, 5-d] pyrimidine derivatives are novel antitumor agents through the inhibition of PI3Kδ.     

New ent-kaurane diterpenes with chiral epoxyangelate moieties from Wedelia prostrata

Four new ent-kaurane diterpenes with chiral epoxyangelate moieties, (2′R,3′R)-3 a- (2′,3′-epoxyangeloyloxy)-kaur-16-en-19-oic acid (1), (2′S,3′S)-3 a- (2′,3′-epoxyangeloyloxy)-kaur-16-en-19-oic acid (2), (2′S,3′R)-3 a- (2',3'-epoxyangeloyloxy)-kaur-16-en-19-oic acid (3) and (2′R,3′S)-3α- (2′,3'-epoxyangeloyloxy)-kaur-16-en-19-oic acid (4), along with eight known diterpenes (5-12), were isolated from Wedelia prostrata. The absolute configurations of the new structures were determined by X-ray crystallography,ECD calculations and chemical methods. All compounds were evaluated for their cytotoxicity activities on human HepG-2 cells,with IC_(50) values of 11.72 ±0.22 μmol/L to 54.75±1.12 μmol/L.     

Cytotoxic polyacetylenes isolated from the roots and rhizomes of Notopterygium incisum

Phytochemical investigation on the roots and rhizomes of Notopterygium incisum led to the isolation of a new polyacetylene, notopolyenol A (1), along with thirteen known analogues (2-14). Their structures were elucidated by extensive analyses of NMR and HRMS data, and the absolute configuration of 1 was unambiguously determined as 3 R by comparison of its retention time and ECD curve with those of synthetic enantiomers (-)-1 and (+)-1, whose absolute configurations were established by using the modified Mosher's method. Subsequent activity screening revealed that (3 S)-1 exhibited the most significant cytotoxicity against MCF-7, H1299, and HepG2 cancer cells with IC_(50) values of 1.3 μmol/L,0.6μmol/L and 1.4μmol/L, respectively.     

Synthesis and biological evaluation of glyco-GA compounds as anticancer agents

A series of novel glyco-gambogic acid（GA） compounds were synthesized and evaluated for their in vitro anti-proliferative activity against human hepatocellular carcinoma（HCC） cells.All compounds showed much better aqueous solubility（0.92- 1.89 mg/mL） than GA（0.013 mg/mL）,and displayed potent inhibition on HCC cells(IC₅₀:0.21-12.23μmol/L) and little affects on non-tumor liver cells(IC₅₀:42.56-86.43μmol/L),suggesting that glyco-GA compounds selectively inhibit HCC proliferation,and may be promising candidates for further intensive study.     

Four new diterpenoid alkaloids with antitumor effect from Aconitum nagarum var. heterotrichum

Four new diterpenoid alkaloids,nagaconitines A-D(1-4),were isolated from the roots of Aconitum nagarum var.heterotrichum.Their structures were elucidated as 8-(4'-hydroxylbutyryl) aconitine(1),15-oxo-13-deoxyludaconitine(2),15-hydroxyldelphisine(3),and 14-hydroxyl-2- acetoxyspiradine C(4)based on extensive UV,IR,MS,1D NMR and 2D NMR analyses.Compounds 3-4 showed inhibition of cancer cell line SK-OV-3 with 31%(IC_(50) 43.78 μmol/L) and 24%(IC_(50) 32.14 μmol/L),respectively.