Studies on the synthesis,in vitro antitumor activity of 4H-benzo[h]chromene, 7H-benzo[h]chromene[2,3-d]pyrimidine derivatives and structure–activity relationships of the 2-,3- and 2,3-positions

Some 4H-benzo[h]chromene and 7H-benzo[h]chromeno[2,3-d]pyrimidine derivatives were prepared as potential cytotoxic agents. The in vitro cytotoxic activity of the synthesized compounds was investigated in comparison with the well-known anticancer standard drugs Vinblastine, Colchicine, and Doxorubicin using MTT colorimetric assay. It was found that compounds 23, 15, 20, and 21 showed the highest anticancer activity against the three tumor cell lines MCF-7, HCT, and HepG-2, compared with Vinblastine and Colchicine, while compound 23 was the most active against HepG-2 as compared with Doxorubicin. We explored the SAR of 4H-benzo[h]chromenes with modification at the 2-,3- positions and 7H-benzo[h]chromeno[2,3-d]pyrimidine at 2,3-positions. The structure–activity relationship (SAR) study revealed that the antitumor activity on 4H-benzo[h]chromene and 7H-benzo[h]chromeno[2,3-d]pyrimidine derivatives were significantly affected by the lipophilicity (hydrophobic or hydrophilic), of the substituent at 2-,3- and 2,3-positions. Structures of these compounds were established on the basis of spectral data, IR, ¹H NMR, ¹³C NMR, ¹³C NMR-DEPT, and MS data.     

Design,synthesis, in silico,and in vitro evaluation of novel benzyloxybenzene substituted (S)-α-amino amide derivatives as cholinesterases and monoaminoxidases inhibitor

In this study, a series of novel benzyloxybenzene substituted (S)-α-amino acid methyl esters and their amide derivatives were synthesized and evaluated for their inhibitory actions against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), monoamine oxidase A (MAO-A), and monoamine oxidase B (MAO-B). The synthetic strategy was based on starting from benzyl bromide ( 5 ) and 4-hydroxybenzaldehyde ( 6 ). The reaction of 5 and 6 in the presence of K₂CO₃ gave benzyloxybenzaldehyde 7. Benzyloxybenzene substituted (S)-α-amino acid methyl esters 11 , 12 , 13 , (±)- 19 , and (±)- 20 were obtained from the reaction of  L -amino acid methyl esters with benzyloxybenzaldehyde ( 7 ) followed by in situ reduction with NaBH₄. The reaction of (S)- 11 , (S)- 12 , 13 , (±)- 19 , and (±)- 20 with excess ammonia gave amides (S)- 14 , (S)- 15 , 16 , (±)- 21 , and (±)- 22 . The in vitro inhibitory activities of compounds against MAO-A, MAO-B, AChE, and BChE were investigated. Within the α-amino acid methyl ester series, 13 (21.32 ± 0.338 µM) showed selectivity by inhibiting the MAO-B better than MAO-A. 13 emerged as the most active member of this series, exhibiting a 12-fold selectivity for MAO-B. 14 (4.501 ± 0.295 µM) demonstrated a pronounced selectivity for MAO-A over MAO-B, with a selectivity ratio of 110-fold. In addition, it was determined that compound 15 (95.65 ± 3.09 µM) had high selectivity for BChE inhibition. 21  was demonstrated the most potent inhibition (18.36 ± 1.36 µM) against AChE.     

Serotonin transporter activity of imidazolidine-2,4-dione and imidazo[2,1-f]purine-2,4-dione derivatives in aspect of their acid–base properties

Affinities of arylpiperazinylalkyl derivatives of imidazo[2,1-f]purine-2,4-dione and imidazolidine-2,4-dione for serotonin transporter and their acid–base properties were evaluated. The dissociation constant (pK _a) of compounds 1–22 were determinated by potentiometric titration and calculated using pKalc 3.1 module of the Pallas system. The data from experimental methods and computational calculations were compared and suitable conclusions were reached.     

Structure-based drug design of a novel family of chalcones as PPARα agonists： virtual screening, synthesis, and biological activities in vitro

Aim： To design and synthesize a novel class of peroxisome proliferator-activated receptors （PPAR）ct agonists, which is obtained by the combination of the classi- cal fibrate “head group”, a linker with appropriate length and a chalcone. Methods： Thirty seven compounds were designed and identified employing the virtual screening approach. Six compounds were then selected for synthesis and bioas- say according to the virtual screening results, structural similarity, and synthetic complexity. Results： Six new compounds （4b and 4d-h） were synthesized and bioassayed. All were found to be potent PPARct agonists, compound 4 h being the most prominent with a 50% effective concentration value of 0.06 μmol/L. Condusion： This study provides a promising novel family of chalcones with a potential hypolipidemic effect.     

Synthesis,characterization, and antibacterial activities of some novel N,N′-disubstituted thiourea, 2-amino thiazole,and imidazole-2-thione derivatives

In the search of bioactive molecules, a series of novel N-substituted thiourea derivatives 3(a–d) are prepared by reaction of the α-amino pyridyl ketone hydrochloride (2a) with the corresponding aryl isothiocyanates. The synthesis of some new 2-amino thiazoles 4(a–d) and imidazole-2-thiones 6(a–d) were attempted by intramolecular cyclization reaction of the N,N′-disubstituted thioureas 3(a–d) and their intermediate ketals 5(a–d) in diluted aqueous acidic and strong acidic mediums. The structure of all newly synthesized compounds was established by analytical and spectral data. The antibacterial studies to all of the synthesized compounds against Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Enterococcus faecalis bacteria with Gram-positive and negative strains, as MIC values are reported. Some of these compounds such as 3a,b,d and 4b,d exhibited a good to significant antibacterial activity. Also, all of new synthesized compounds 3,4,6(a–d) were active against Gram-positive S. aureus bacterium. Thus, some of these compounds can emerge as a promising tool for further research work.     

Design,synthesis, and biological evaluation of some novel naphthoquinone-glycine/β-alanine anilide derivatives as noncovalent proteasome inhibitors

A series of novel noncovalent glycine/β-alanine anilide derivatives possessing 2-chloronaphthoquinone structure as a pharmacophoric unit were designed, synthesized, and evaluated for their antiproliferative and antiproteasomal activities against MCF-7 cell line, in vitro. According to biological activity results, all the target compounds showed antiproliferative activity in the range of IC₅₀ = 7.10 ± 0.10–41.08 ± 0.14 μM and most of them exhibited inhibitory efficacy with varying ratios against the three catalytic subunits (β1, β2, and β5) presenting caspase-like (C-L), trypsin-like (T-L) and chymotrypsin-like (ChT-L) activities of proteasome. The antiproteasomal activity evaluations revealed that compounds preferentially inhibited the β5 subunit compared with β1 and β2 subunits of the proteasome. Among the compounds, compounds 7 and 9 showed the highest antiproliferative activity with an IC₅₀ value of 7.10 ± 0.10 and 7.43 ± 0.25 μM, respectively. Additionally, compound 7 displayed comparable potency to PI-083 lead compound in terms of β5 antiproteasomal activity with an inhibition percentage of 34.67 at 10 μM. This compound showed an IC₅₀ value of 32.30 ± 0.45 μM against β5 subunit. Furthermore, molecular modeling studies of the most active compound 7 revealed key interactions with β5 subunit. The results suggest that this class of compounds may be beneficial for the development of new potent proteasome inhibitors.     

Synthesis and structure–activity relationship studies on novel 8-amino-3-[2-(4-fluorophenoxy)ethyl]-1,3-diazaspiro[4.5]decane-2,4-dione derivatives as anticonvulsant agents

A series of novel 8-amino-3-[2-(4-fluorophenoxy)ethyl]-1,3-diazaspiro[4.5]decane-2,4-dione derivatives 7–36 was synthesized and their pharmacological activity was determined with the objective to better understand their structure–activity relationship for anticonvulsant activity. All the compounds were evaluated for their possible anticonvulsant activity by maximal electroshock seizure (MES) test and their neurotoxic effects were determined by rotarod test. Majority of the compounds were active in MES tests. Compounds 24, 27, and 34 showed a significant and protective effect on seizure, when compared with standard drug phenytoin. The compounds having amide bond showed moderate protective effect on MES induced seizures compared to sulfonamide.     

Metabolic fate of sipoglitazar, a novel oral PPAR agonist with activities for PPAR-γ, -α and -δ, in rats and monkeys and comparison with humans in vitro

Sipoglitazar is a novel anti-diabetic agent with triple agonistic activities on the human peroxisome proliferator-activated receptors, hPPAR-γ, -α, and -δ. The bioavailability for sipoglitazar was 95.0% and 72.6% in rats and monkeys respectively and sipoglitazar is hardly subject to first pass metabolism in either species. Following oral administration of [1?C]sipoglitazar to rats, sipoglitazar and its metabolites were distributed to the rat tissues with relatively high concentrations in the liver and also to the target tissue, the adipose tissue. The major component was sipoglitazar in the plasma of rats and monkeys. In rats, sipoglitazar was mainly excreted into the feces via biliary excretion as sipoglitazar-G, while the major component was M-I-G in the urine and M-I in the feces of monkeys. In hepatocytes, the metabolism was not extensively advanced in rats and the main metabolites were M-I and sipoglitazar-G in humans, similar to the metabolic profile in monkeys. There was no metabolite specific for humans in vitro. In conclusion, the formation of M-I, M-I-G and sipoglitazar-G is considered to be crucial and sipoglitazar is presumed to be cleared primarily by oxidation and glucuronidation in humans, when examined in vivo and in vitro.     

Derivatives of （phenylsulfonamido-methyl）nicotine and （phenylsulfonamido-methyl）thiazole as novel 11β-hydroxysteroid dehydrogenase type 1 inhibitors： synthesis and biological activities in vitro

Aim： To design and synthese a novel class of 11β-hydroxysteroid dehydrogenase type 1 （11β-HSD1） inhibitors, featuring the （phenylsul- fonamido-methyl）pyridine and （phenylsulfonamido-methyl）thiazole framework. Methods： Our initial lead 4-（phenylsulfonamido-methyl）benzamides were modified. Inhibition of human and mouse 11β-HSD1 enzymatic activities by the new compounds was determined by a scintillation proximity assay （SPA） using microsomes containing 11β- HSDI. Results： Sixteen new compounds （6a-6h, 7a-7h） were designed, synthesized and bioassayed. In dose-response studies, several compounds showed strong inhibitory activities with IC50 values at nanomolar or low nanomolar concentrations. Structure-activity relationships are also discussed with respect to molecular docking results. Conclusion： This study provides two promising new templates for 11β-HSD1 inhibitors.     

Absorption, distribution, metabolism, and excretion of [1-¹⁴C]-perfluorohexanoate ([¹⁴C]-PFHx) in rats and mice

The absorption, tissue distribution, elimination, and metabolism of [1-¹⁴C]-PFHx in rats and mice dosed orally at 2 or 100 mg/kg was evaluated following a single dose or after 14 consecutive doses. Absorption was rapid in rats as evidenced by a short time to maximum concentration (C_max) of 30 min in male rats and 15 min in female rats at both the 2 and 100 mg/kg dose level. The plasma elimination half-life was somewhat longer in males (1.5-1.7 h) than in females (0.5-0.7 h). Absorption in the mouse was also rapid with the maximum plasma concentration occurring between 15 and 30 min after dosing. The maximum concentration was not appreciably different between male and female mice (8 μg equiv./g at 2 mg/kg; ∼350 μg equiv./g at 100 mg/kg). The primary route of elimination was via the urine. PFHx was not metabolized in rat or mouse hepatocytes, nor were any metabolites observed after oral dosing in either rodent species. Essentially 100% of the dose was eliminated in urine within 24 h demonstrating that PFHx is readily absorbed and bioavailability approaches 100%, even at a dose as high as 100 mg/kg. The route and extent of elimination was unchanged after 14 days of daily dosing. Tissues were collected at three time points (rat: 0.5, 2, and 24 h; mice: 0.25, 1, and 24 h) after dosing to investigate the tissue clearance kinetics of PFHx following a single dose at 2 or 100 mg/kg. In all tissues except skin, PFHx was not quantifiable 24 h after dosing in both sexes of the two species.     

1-[2-(2,4-二氟苯基)-2,3-环氧丙基]-1H-1,2,4-三唑甲烷磺酸盐的合成

1- [2 - ( 2 ,4-二氟苯基 ) - 2 ,3-环氧丙基 ]- 1 H- 1 ,2 ,4-三唑甲烷磺酸盐 ( 1 )是合成氟康唑等抗真菌药物的关键中间体。文献 [1]以间二氟苯 ( 2 )为原料 ,与氯乙酰氯反应生成 α-氯 - 2 ,4-二氟苯乙酮 ( 3) ,3在甲苯中与三唑反应生成 2 ,4-二氟 - α- ( 1 H- 1 ,2 ,4-三唑 - 1 -基 )苯乙酮 ( 4 ) ,4与 ylid试剂碘化三甲基硫盐反应形成环氧化物 ,再与甲磺酸成盐得到 1。此法第 2步和第 3步收率均很低 ,分别为 8.7%和2 1 .84% ,成品生产成本较高。本文参照文献 [2 ]的相转移催化三唑烷基化方法 ,以 TEBA为相转移催化剂 ,K2 CO3 为…     

Pharmacokinetics and metabolism of N-[N-[3-(3-hydroxy-4-methoxyphenyl) propyl]-α-aspartyl]-L-phenylalanine 1-methyl ester, monohydrate (advantame) in the rat, dog, and man

The pharmacokinetics and metabolism of advantame were evaluated in rats, dogs, and humans. The oral pharmacokinetic studies using (14)C-advantame showed that advantame undergoes rapid but incomplete absorption, with an oral bioavailability of total radioactivity in the range of 4-23%. Data indicated that absorption was mainly as ANS9801-acid (de-esterified advantame), which was formed in the gastrointestinal tract as a result of the hydrolysis of the methyl ester group of the parent compound. In the dog, plasma ANS9801-acid was present largely in the form of an unidentified conjugate. Advantame (chiefly in the form of metabolites) was mainly excreted in the feces in rats, dogs, and humans (>80% in each species), with urinary excretion representing a minor route. The predominant metabolite of (14)C-advantame detected in the feces and the urine of rats, dogs, and humans was ANS9801-acid, with lower amounts of 3-[3-hydroxy-4-methoxyphenyl]-1-propylamine (termed HU-1) or N-(3-(3-hydroxy-4-methoxy phenyl))propyl-L-aspartic acid (termed HF-1) present, as well as other minor metabolites and areas of indistinct radioactivity. ANS9801-acid, HU-1, and HF-1 were detected and identified in the urine of rats, humans, and dogs, while ANS9801-acid and HF-1 were identified in the feces of humans and dogs. In the feces of rats, in addition to ANS9801-acid, other additional metabolites were detected, including demethylated ANS9801-acid (designated as RF-1) and another unidentified metabolite (designated as RF-2). Overall, the data show generally similar pharmacokinetics of advantame and ANS9801-acid in animals and in humans and close similarity with neotame. Metabolites of advantame that occur in humans are also found in the 2 species utilized in the toxicology studies, and the metabolism studies support the interpretation of safety data from studies conducted in rats and dogs.     

Design and evaluation of polyamidoamine dendrimer conjugate with PEG, α-cyclodextrin and lactose as a novel hepatocyte-selective gene carrier in vitro and in vivo

Abstract

To develop a novel hepatocyte-selective gene carrier, we prepared polyamidoamine starburst dendrimer (generation 3, G3) conjugates with three functional molecules, i.e. α-cyclodextrin, polyethylene glycol (PEG, molecular weight?=?2170) and lactose (PEG-LαCs), and evaluated gene delivery efficiency of these conjugates in vitro and in vivo. PEG-LαC (G3, degrees of substitution of the PEG moiety (DSP) 2.1) showed higher gene transfer activity than other PEG-LαCs (G3, DSP4.0, 6.2) in HepG2 cells, expressing asialoglycoprotein receptor, and the activity decreased in HeLa cells, non-expressing the receptor and in the presence of asialofetuin. High gene transfer activity of PEG-LαC (G3, DSP2.1) was retained even in the presence of 50% serum, although the activity of α-cyclodextrin/lactosylated dendrimer (G3) conjugate (Lac-α-CDE (G3)), which is lacking a PEG moiety, was severely decreased in the presence of 20% serum. PEG-LαC (G3, DSP2.1) provided negligible cytotoxicity up to a charge ratio of 50 (carrier/pDNA) in HepG2 cells and less acute organ toxicity. PEG-LαC (G3, DSP2.1) showed selective gene transfer activity to hepatic parenchymal cells rather than hepatic non-parenchymal cells. These results suggest that PEG-LαC (G3, DSP2.1) is useful as a hepatocyte-selective gene carrier in vitro and in vivo.     

Uterotrophic assay,Hershberger assay,and subacute oral toxicity study of 4,4´-[1-[4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl]ethylidene]bis[phenol] based on the OECD draft protocols

We performed an uterotrophic assay, the Hershberger assay, and a 28-day repeated-dose toxicity study (enhanced OECD test guideline No. 407) of 4,4′-[1-[4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl]ethylidene]bis[phenol] based on the OECD draft protocols. In the uterotrophic assay, female SD rats were subcutaneously injected with the chemical at doses of 0, 100, 300, and 1,000 mg/kg on each of 3 days from postnatal day 20 to day 22, and the uterine weight of rats given the 1,000 mg/kg dose of the test chemical plus ethinyl estradiol decreased. In the Hershberger assay, the test chemical was orally administered at doses of 0, 100, 300, and 1,000 mg/kg day to castrated male SD rats for ten consecutive days beginning on postnatal day 56, and no changes were observed. On the other hand, when the test chemical was orally administered at doses 0, 100, 300, and 1,000 mg/kg day for at least 28 days, a decrease in LH values in rats of both sexes and a decrease in FSH and estradiol values in female rats were detected in the 1,000 mg/kg group, and abnormal estrous cycles, uterine glandular atrophy, persistence of ovarian corpora lutea, vaginal epithelial mucification, and mammary glandular hyperplasia were also observed in one female rat in the 1,000 mg/kg group. Therefore, the uterotrophic assay used in this study showed that the chemical has the estrogen–antagonist properties, and some potentially endocrine-mediated effects were detected in growing rats based on the results of the enhanced OECD test guideline No. 407. However, the changes were observed in rats given a high dose of the chemical, 1,000 mg/kg day.     

Pyridazine and its related compounds. Part 36. Synthesis and antimicrobial activity of some novel pyrimido[4′,5′:4,5]thieno[2,3-c]pyridazine derivatives

Novel derivatives of pyrimidothienopyridazine were designed and synthesized through a versatile method. Some of the target compounds bearing the sulfonamide group were evaluated for their antimicrobial activity against representative Gram-positive bacteria, Gram-negative bacteria, and fungi by applying the agar plate diffusion technique. The results showed that derivatives 11a have promising inhibitory activity against Gram-positive bacteria, and derivatives 11b and 11e have also potent inhibition against fungi. Rest of the compounds showed moderate to low activity against the examined micro-organisms.     

In vitro and in vivo assessment of the mutagenic activity of N-[N-[3-(3-hydroxy-4-methoxyphenyl) propyl]-α-aspartyl]-L-phenylalanine 1-methyl ester, monohydrate (advantame)

Advantame (N-[N-[3-(3-hydroxy-4-methoxyphenyl) propyl]-α-aspartyl]-L-phenylalanine 1-methyl ester, monohydrate), an N-substituted analogue of aspartame, has been developed as a high-intensity sweetener. It is approximately 100 and 20,000 times sweeter than aspartame and sucrose, respectively. In this study the safety of advantame has been evaluated using a series of in vitro and in vivo genotoxicity assays including, bacterial mutation, mammalian cell mutation, and mouse micronucleus tests. Advantame did not induce reverse mutations in Salmonella typhimurium and Escherichia coli at concentrations of up to 5000 μg/plate. In the mammalian cell mutation assay, advantame did not induce mutation at the Hprt locus of L5178Y mouse lymphoma cells in two independent experiments, either in the absence or presence of S9. In vivo, there was no effect on the incidence of micronucleated immature or mature erythrocytes in bone marrow after oral administration of the test substance at any dose level (up to 2000 mg/kg body weight) or sampling time (24 and 48 h). The results of these studies demonstrate that advantame is without genotoxic potential.     

Synthesis and in?vitro antimicrobial activity of benzo[b][1,4]thiazin-3(4H)-ones via smiles rearrangement

New benzo[b][1,4]thiazin-3(4H)-one derivatives (compounds 12a–p) were synthesized via Smiles rearrangement and assayed in vitro for their antimicrobial activity against Gram-positive, Gram-negative bacteria and fungi. The antimicrobial activity of the benzo[b][1,4]thiazin-3(4H)-ones showed, on the whole, potent toward all tested Gram-positive and Gram-negative microorganism (minimal inhibitory concentration ranging from 16 to 64 μg/ml), whereas weak effectiveness was exhibited against fungi. Data obtained suggested that 12g, 12i, and 12o exerted the best antibacterial activity against Gram-positive bacteria and compound 12b demonstrated the best inhibition of Gram-negative bacteria. These observations provide some predictions to design further antimicrobial active compounds prior to their synthesis following with molecular modeling studies.