Designed multiple ligands for the treatment of type 2 diabetes mellitus and its complications: Discovery of (5-arylidene-4-oxo-2-thioxothiazolidin-3-yl)alkanoic acids active as novel dual-targeted PTP1B/AKR1B1 inhibitors.

Type 2 diabetes mellitus (T2DM) is a serious chronic disease with an alarmingly growing worldwide prevalence. Current treatment of T2DM mainly relies on drug combinations in order to control blood glucose levels and consequently prevent the onset of hyperglycaemia-related complications. The development of multiple-targeted drugs recently emerged as an attractive alternative to drug combinations for the treatment of complex diseases with multifactorial pathogenesis, such as T2DM. Protein tyrosine phosphatase 1B (PTP1B) and aldose reductase (AKR1B1) are two enzymes crucially involved in the development of T2DM and its chronic complications and, therefore, dual inhibitors targeted to both these enzymes could provide novel agents for the treatment of this complex pathological condition. In continuing our search for dual-targeted PTP1B/AKR1B1 inhibitors, we designed new (5-arylidene-4-oxo-2-thioxothiazolidin-3-yl)alkanoic acids. Among them, 3-(4-phenylbutoxy)benzylidene derivatives 6f and 7f, endowed with interesting inhibitory activity against both targets, proved to control specific cellular pathways implicated in the development of T2DM and related complications.

Design, synthesis, and preliminary pharmacological evaluation of novel thiazolidinone derivatives as potential benzodiazepine agonists.

Thiazolidinones are well-known heterocycles that demonstrate promising biological effects such as anticonvulsant activity. Hybridization of these chemicals with scaffold, which has necessary pharmacophores for binding to the benzodiazepine receptors, can prompt a novel structure possessing extensive anticonvulsant effects. In this study, novel derivatives of thiazolidinone as new benzodiazepine agonists were designed, synthesized, and biologically evaluated. Compound 5h, 4-chloro-2-(2-fluorophenoxy)-N-(4-oxo-2-(p-tolyl)thiazolidin-3-yl)benzamide, exhibited considerable anticonvulsant activity, proper sedative-hypnotic effect, no memory impairment, and no muscle relaxant effect. The pharmacological effects of the designed compounds were antagonized by flumazenil, which confirmed the benzodiazepine receptors' involvement in their biological effects. Based on in silico calculations of ADME properties of our novel compounds, they could be active oral agents potentially. In this study, we designed novel structures by the hybridization of thiazolidinone moiety with scaffold which has necessary pharmacophores for binding to the benzodiazepine receptors. The results are very promising for developing new lead compounds as benzodiazepine agonists possess anticonvulsant effects.

Design, synthesis, and anticancer activity of novel 4-thiazolidinone-phenylaminopyrimidine hybrids.

4-Thiazolidinones and phenylaminopyrimidines are known as anticancer agents. Imatinib is the pioneer phenylaminopyrimidine derivative kinase inhibitor, which is used for the treatment of chronic myeloid leukemia. With a hybrid approach, a novel series of 5-benzylidene-2-arylimino-4-thiazolidinone derivatives containing phenylaminopyrimidine core were designed, synthesized, and tested for their anticancer activity on K562 (chronic myeloid leukemia), PC3 (prostat cancer), and SHSY-5Y (neuroblastoma) cells. Since superior anticancer activity was observed on K562 cells, further biological studies of selected compounds (8, 15, and 34) were performed on K562 cells. For the synthesis of designed compounds, thiourea compounds were converted to 2-imino-1,3-thiazolidin-4-ones with α-chloroacetic acid in the presence of sodium acetate. 5-Benzylidene-2-imino-1,3-thiazolidin-4-one derivatives were obtained by Knoevenagel condensation of 2-imino-1,3-thiazolidin-4-ones with related aldehydes. Compounds 8, 15, and 34 were evaluated for cell viability, apoptosis studies, cell cycle experiments, and DNA damage assays. IC50 values of compounds 8, 15, and 34 were found as 5.26 ± 1.03, 3.52 ± 0.91, and 8.16 ± 1.27 µM, respectively, in K562 cells. Preferably, these compounds showed less toxicity towards L929 cells compared to imatinib. Furthermore, compounds 8 and 15 significantly induced early and late apoptosis in a time-dependent manner. Compounds 15 and 34 induced cell cycle arrest at G0/G1 phase and compound 8 caused cell cycle arrest at G2/M phase. Based on DNA damage assay, compounds 8 and 15 were found to be more genotoxic than imatinib towards K562 cells. To put more molecular insight, possible Abl inhibition mechanisms of most active compounds were predicted by molecular docking studies. In conclusion, a novel series of 5-benzylidene-2-arylimino-4-thiazolidinone derivatives and their promising anticancer activities were reported herein.

Antimicrobial properties of heterocyclic compounds against clinical mastitis isolates

ABSTRACT: Mastitis causes significant economic losses to the dairy cattle industry. The present study aimed to evaluate the antibacterial properties of 39 heterocyclic derivatives (1,3-thiazoles and 4-thiazolidinones) against clinical mastitis isolates from dairy cows. Milk samples were collected from cows with clinical mastitis and the bacterial species were identified by PCR. Antibacterial activity was assessed using the broth microdilution method. First, 39 heterocyclic compounds were tested against four bacterial isolates (Staphylococcus aureus, Streptococcus agalactiae, Corynebacterium bovis and Escherichia coli) randomly chosen from those recovered from the milk samples (Study 1). Subsequently, the compounds with the strongest antibacterial activity were tested against all the bacterial isolates recovered from the milk samples (Study 2). 1,3-thiazoles showed the strongest antibacterial activity, specially compounds 30 and 38, which also showed bactericidal properties according to their minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values. Corynebacterium spp. and Enterobacteriaceae isolates were the most susceptible to compounds 30 and 38. Compounds 30 and 38 are promising targets for new antimicrobial agents.

RESUMO: A mastite causa significativas perdas econômicas à indústria leiteira bovina. O presente estudo teve como objetivo avaliar as propriedades antibacterianas de 39 derivados heterocíclicos (1,3-tiazóis e 4-tiazolidinonas) contra isolados clínicos de mastite em vacas leiteiras. Amostras de leite foram coletadas de vacas com mastite clínica e as espécies bacterianas isoladas foram identificadas por PCR. A atividade antibacteriana foi avaliada pelo método de microdiluição em caldo. Primeiramente, os 39 compostos heterocíclicos foram testados contra quatro isolados bacterianos (Staphylococcus aureus, Streptococcus agalactiae, Corynebacterium bovis e Escherichia coli) escolhidos aleatoriamente dentre os recuperados das amostras de leite (Estudo 1). Posteriormente, compostos com atividade antibacteriana mais forte foram testados contra todos os isolados bacterianos recuperados das amostras de leite (Estudo 2). Os compostos 1,3-tiazóis apresentaram a maior atividade antibacteriana, principalmente os compostos 30 e 38, que também apresentaram propriedades bactericidas de acordo com seus valores de concentração inibitória mínima (CIM) e concentração bactericida mínima (CBM). Os isolados Corynebacterium spp. e Enterobacteriaceae foram os mais suscetíveis aos compostos 30 e 38. Os compostos 30 e 38 mostraram-se promissores como novos agentes antimicrobianos.

Antimicrobial properties of heterocyclic compounds against clinical mastitis isolates / Propriedades antimicrobianas de compostos heterocíclicos contra isolados de mastite clínica

Mastitis causes significant economic losses to the dairy cattle industry. The present study aimed to evaluate the antibacterial properties of 39 heterocyclic derivatives (1,3-thiazoles and 4-thiazolidinones) against clinical mastitis isolates from dairy cows. Milk samples were collected from cows with clinical mastitis and the bacterial species were identified by PCR. Antibacterial activity was assessed using the broth microdilution method. First, 39 heterocyclic compounds were tested against four bacterial isolates (Staphylococcus aureus, Streptococcus agalactiae, Corynebacterium bovis and Escherichia coli) randomly chosen from those recovered from the milk samples (Study 1). Subsequently, the compounds with the strongest antibacterial activity were tested against all the bacterial isolates recovered from the milk samples (Study 2). 1,3-thiazoles showed the strongest antibacterial activity, specially compounds 30 and 38, which also showed bactericidal properties according to their minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values. Corynebacterium spp. and Enterobacteriaceae isolates were the most susceptible to compounds 30 and 38. Compounds 30 and 38 are promising targets for new antimicrobial agents.(AU)

A mastite causa significativas perdas econômicas à indústria leiteira bovina. O presente estudo teve como objetivo avaliar as propriedades antibacterianas de 39 derivados heterocíclicos (1,3-tiazóis e 4-tiazolidinonas) contra isolados clínicos de mastite em vacas leiteiras. Amostras de leite foram coletadas de vacas com mastite clínica e as espécies bacterianas isoladas foram identificadas por PCR. A atividade antibacteriana foi avaliada pelo método de microdiluição em caldo. Primeiramente, os 39 compostos heterocíclicos foram testados contra quatro isolados bacterianos (Staphylococcus aureus, Streptococcus agalactiae, Corynebacterium bovis e Escherichia coli) escolhidos aleatoriamente dentre os recuperados das amostras de leite (Estudo 1). Posteriormente, compostos com atividade antibacteriana mais forte foram testados contra todos os isolados bacterianos recuperados das amostras de leite (Estudo 2). Os compostos 1,3-tiazóis apresentaram a maior atividade antibacteriana, principalmente os compostos 30 e 38, que também apresentaram propriedades bactericidas de acordo com seus valores de concentração inibitória mínima (CIM) e concentração bactericida mínima (CBM). Os isolados Corynebacterium spp. e Enterobacteriaceae foram os mais suscetíveis aos compostos 30 e 38. Os compostos 30 e 38 mostraram-se promissores como novos agentes antimicrobianos.(AU)

An investigation on 4-thiazolidinone derivatives as dual inhibitors of aldose reductase and protein tyrosine phosphatase 1B, in the search for potential agents for the treatment of type 2 diabetes mellitus and its complications.

Designed multiple ligands (DMLs), developed to modulate simultaneously a number of selected targets involved in etiopathogenetic mechanisms of a multifactorial disease, such as diabetes mellitus (DM), are considered a promising alternative to combinations of drugs, when monotherapy results to be unsatisfactory. In this work, compounds 1-17 were synthesized and in vitro evaluated as DMLs directed to aldose reductase (AR) and protein tyrosine phosphatase 1B (PTP1B), two key enzymes involved in different events which are critical for the onset and progression of type 2 DM and related pathologies. Out of the tested 4-thiazolidinone derivatives, compounds 12 and 16, which exhibited potent AR inhibitory effects along with interesting inhibition of PTP1B, can be assumed as lead compounds to further optimize and balance the dual inhibitory profile. Moreover, several structural portions were identified as features that could be useful to achieve simultaneous inhibition of both human AR and PTP1B through binding to non-catalytic regions of both target enzymes.

Novel 4-thiazolidinone derivatives as agonists of benzodiazepine receptors: Design, synthesis and pharmacological evaluation.

A new series of 4-chloro-N-(2-(substitutedphenyl)-4-oxothiazolidin-3-yl)-2-phenoxybenzamide derivatives were designed, synthesized and biologically evaluated as anticonvulsant agents. The designed compounds have the main essential functional groups for binding to the benzodiazepine receptors and 4-thiazolidinone ring as an anticonvulsant pharmacophore. Some of the new synthesized compounds showed considerable anticonvulsant activity in electroshock and pentylenetetrazole-induced lethal convulsion tests. Compound 5i, 4-chloro-N-(2-(4-methoxyphenyl)-4-oxothiazolidin-3-yl)-2-phenoxybenzamide, with the best activity was selected for evaluation of other benzodiazepine pharmacological effects. This compound induced significant sedative-hypnotic activity. However, it does not impair the learning and memory in the experimental condition. Flumazenil was able to antagonize the sedative-hypnotic and anticonvulsant effects of compound 5i indicating that benzodiazepine receptors are highly involved in the pharmacological properties of the novel compounds.

Discovery of 4-[(5-arylidene-4-oxothiazolidin-3-yl)methyl]benzoic acid derivatives active as novel potent allosteric inhibitors of protein tyrosine phosphatase 1B: In silico studies and in vitro evaluation as insulinomimetic and anti-inflammatory agents.

New 4-{[5-arylidene-2-(4-fluorophenylimino)-4-oxothiazolidin-3-yl]methyl}benzoic acids (5) and 2-thioxo-4-thiazolidinone analogues (6) were synthesised as a part of a continuing search for new inhibitors of protein tyrosine phosphatase 1B (PTP1B), an enzyme which is implicated in metabolic disorders and inflammatory signaling. Most of the tested compounds were shown to be potent PTP1B inhibitors. Moreover, their inhibition mechanism was markedly influenced by the substituents in the positions 2 and 5, as kinetic studies indicated. Docking experiments suggested that certain derivatives 5 and 6 may efficiently fit into an allosteric site positioned between the ß-sheet including Leu71 and Lys73 and a lipophilic pocket closed by the loop consisting of Pro210 to Leu 204. In cellular assays, several of these new 4-thiazolidinone derivatives showed insulinomimetic and anti-inflammatory properties. Out of them, compound 5b exhibited the most promising profile, being able to promote the activation of both insulin receptor and downstream Akt protein as well as to increase 2-deoxyglucose cellular uptake. Interestingly, compound 5b was also able to interrupt critical events in inflammatory signaling.

The interaction of 4-thiazolidinone derivatives containing indolin-2-one moiety with P-glycoprotein studied using K562 cell lines.

P-glycoprotein (P-gp) is an active drug efflux pump, which exists widely in various MDR tumor cells, conferring drug resistance to tumor cells during chemotherapy. Some 4-thiazolidinone derivatives containing indolin-2-one moiety are novel anti-tumor compounds. The aim of this study was to evaluate the transport activity of P-gp towards 4-thiazolidinone derivatives containing indolin-2-one moiety (as mixtures of 2Z, 5Z and 2E, 5Z isomers) and the transport inhibition activities of the derivatives to P-gp, the results of which could provide crucial information for the further separation of and development on the derivatives with excellent anti-tumor activities. The results indicate that the further separation and development should be focused on compounds 7, 10, 12 and 13 (tumor cell cytotoxic P-gp modulators) and compounds 8, 9, 17 and 18 (non-substrates of P-gp), which exhibit anti-tumor activities and could overcome P-gp mediated MDR. Furthermore, the results of molecular docking indicate that Ser222, a residue in TM4 domain of P-gp, exhibits an intriguing feature in that it interacts with all of the derivatives related with P-gp transport in a significant way, including both typical substrates and modulators of P-gp. Meanwhile, the compounds showing no interaction with Ser222 are mainly from the category of non-substrates of P-gp. Therefore, the interaction between Ser222 and the tested derivative would provide useful information for the further development on 4-thiazolidinone derivatives containing indolin-2-one moiety.

Structure-activity relationships and molecular modelling of new 5-arylidene-4-thiazolidinone derivatives as aldose reductase inhibitors and potential anti-inflammatory agents.

A series of 5-(carbamoylmethoxy)benzylidene-2-oxo/thioxo-4-thiazolidinone derivatives (6-9) were synthesized as inhibitors of aldose reductase (AR), enzyme which plays a crucial role in the development of diabetes complications as well as in the inflammatory processes associated both to diabetes mellitus and to other pathologies. In vitro inhibitory activity indicated that compounds 6-9a-d were generally good AR inhibitors. Acetic acid derivatives 8a-d and 9a-d were shown to be the best enzyme inhibitors among the tested compounds endowed with significant inhibitory ability levels reaching submicromolar IC50 values. Moreover, some representative AR inhibitors (7a, 7c, 9a, 9c, 9d) were assayed in cultures of human keratinocytes in order to evaluate their capability to reduce NF-kB activation and iNOS expression. Compound 9c proved to be the best derivative endowed with both interesting AR inhibitory effectiveness and ability to reduce NF-kB activation and iNOS expression. Molecular docking and molecular dynamics simulations were undertaken to investigate the binding modes of selected compounds into the active site of AR in order to rationalize the inhibitory effectiveness of these derivatives.

Optimization of 2-(3-(arylalkyl amino carbonyl) phenyl)-3-(2-methoxyphenyl)-4-thiazolidinone derivatives as potent antitumor growth and metastasis agents.

A series of 2,3-diaryl-4-thiazolidinone derivatives were synthesized and evaluated for their antiproliferative properties against two well-known cancer cell lines (A549 as human lung cancer and MDA-MB-231 as human breast cancer). Structure activity relationship (SAR) analysis resulted in the discovery of 2-(3-(arylalkyl amino carbonyl)phenyl)-3-(2-methoxy-phenyl)-4-thiazolidinone derivatives with high potent inhibitory effects on the proliferation of both cancer cell lines. Furthermore, several compounds with potent antiproliferative activities displayed excellent inhibitory activities on migration with an IC50 of about 0.05 µM on MDA-MB-231 cells in two different migration assays. In particular, compound 39 was indicated to suppress tumor growth and metastasis as well as promote survival rate. Intriguingly, this series of analogs have been indicated to inhibit tumor cell proliferation through inducing cell cycle arrest. These results suggested that the new series of 2-(3-(arylalkyl amino carbonyl)phenyl)-3-(2-methoxyphenyl)-4-thiazolidinone derivatives could be regarded and developed as novel highly potential anticancer agents in the future.

Synthesis, biological activity and structure-activity relationships of new benzoic acid-based protein tyrosine phosphatase inhibitors endowed with insulinomimetic effects in mouse C2C12 skeletal muscle cells.

Insulin resistance is a complex altered metabolic condition characterized by impaired insulin signaling and implicated in the pathogenesis of serious human diseases, such as diabetes, obesity, neurodegenerative pathologies. In pursuing our aim to identify new agents able to improve cellular insulin sensitivity, we have synthesized new 4-[(5-arylidene-4-oxo-2-phenylimino/oxothiazolidin-3-yl)methyl]benzoic acids (5, 8) and evaluated their inhibitory activity towards human protein tyrosine phosphatases PTP1B, LMW-PTP and TCPTP, enzymes which are involved in the development of insulin resistance. Compounds 5 and 8 showed from moderate to significant selectivity toward PTP1B over both the highly homologous TCPTP and the two isoforms of human LMW-PTP. In addition, most of the tested compounds selectively inhibited LMW-PTP IF1 over the isoform IF2. Docking studies into the active sites of PTP1B and LMW-PTP aided the rationalization of the observed PTP inhibitory profile. Moreover, most tested compounds were capable to induce the insulin metabolic pathway in mouse C2C12 skeletal muscle cells by remarkably stimulating both IRß phosphorylation and 2-deoxyglucose cellular uptake.