Design and Synthesis of Pyrazole-3-one Derivatives as Hypoglycaemic Agents

Pyrazole-3-one compounds were designed on the basis of docking studies of previously reported antidiabetic pyrazole compounds. The amino acid residues found during docking studies were used as guidelines for the modification of aromatic substitutions on pyrazole-3-one structure. Depending on the docking score, the designed compounds were selectively prioritized for synthesis. The synthesized compounds were subjected to in vivo hypoglycemic activity using alloxan induced diabetic rats and metformin as a standard. Compound 4 having sulphonamide derivative was found to be the most potent compound among the series.

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An Evaluation of 3-Rhamnosylquercetin, a Glycosylated Form of Quercetin, against the Myotoxic and Edematogenic Effects of sPLA2fromCrotalus durissus terrificus

BioMed Research International ◽

10.1155/2014/341270 ◽

2014 ◽

Vol 2014 ◽

pp. 1-11 ◽

Cited By ~ 6

Author(s):

Daniela de Oliveira Toyama ◽

Henrique Hessel Gaeta ◽

Marcus Vinícius Terashima de Pinho ◽

Marcelo José Pena Ferreira ◽

Paulete Romoff ◽

...

Keyword(s):

Amino Acid ◽

Docking Studies ◽

Pharmacological Effects ◽

Amino Acid Residues ◽

Substrate Molecule ◽

Pharmacological Activities ◽

Potent Inhibition ◽

Crotalus Durissus

This paper shows the results of quercitrin effects on the structure and biological activity of secretory phospholipase (sPLA2) fromCrotalus durissus terrificus, which is the main toxin involved in the pharmacological effects of this snake venom. According to our mass spectrometry and circular dichroism results, quercetin was able to promote a chemical modification of some amino acid residues and modify the secondary structure ofC. d. terrificussPLA2. Moreover, molecular docking studies showed that quercitrin can establish chemical interactions with some of the crucial amino acid residues involved in the enzymatic activity of the sPLA2, indicating that this flavonoid could also physically impair substrate molecule access to the catalytic site of the toxin. Additionally,in vitroandin vivoassays showed that the quercitrin strongly diminished the catalytic activity of the protein, altered its Vmax and Km values, and presented a more potent inhibition of essential pharmacological activities in theC. d. terrificussPLA2, such as its myotoxicity and edematogenic effect, in comparison to quercetin. Thus, we concluded that the rhamnose group found in quercitrin is most likely essential to the antivenom activities of this flavonoid againstC. d. terrificussPLA2.

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Synthesis, Hypoglycemic Effect, Antimicrobial and Molecular Docking Studies of Organotin(IV) Complexes Derived from N-Phthalimido β-Amino Acid Derivatives

Journal of the Brazilian Chemical Society ◽

10.21577/0103-5053.20210011 ◽

2021 ◽

Author(s):

Muhammad Ahmed ◽

Nagina Riaz ◽

Muhammad Kashif ◽

Muhammad Ashfaq ◽

Muhammad Arshad ◽

...

Keyword(s):

Molecular Docking ◽

Amino Acid ◽

Docking Studies ◽

Hypoglycemic Agents ◽

Amino Acid Derivatives ◽

Propanoic Acid ◽

Ionization Mass ◽

Amino Acid Residues ◽

Diabetic Rabbits

N-Phthalimido β-amino acid derivatives, 3-phthalimido-3(2-hydroxyphenyl) propanoic acid (P2HPA) and 3-phthalimido-3(2-nitrophenyl) propanoic acid (P2NPA) with new series of diand triorganotin(IV) complexes (1-12) have been designed and synthesized. All the ligands and organotin(IV) complexes were characterized by elemental analysis, Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (1H, 13C, 119Sn) spectroscopy and electron ionization mass spectrometry (EI-MS). Synthesized ligands and complexes were screened to determine the antibacterial activity and results showed that the triorganotin(IV) complexes have better activity compared to diorganotin(IV) complexes and ligands. In addition, molecular docking analysis of ligands on the catalytic pocket of sortase A (PDB ID 1T2W) showed that the ligands can bind the active amino acid residues in the pocket. The antioxidant activity was also performed by the DPPH (1,1-diphenyl-2-picrylhydrazyl radical) method and complexes showed better results than ligands. The compounds were also tested in vivo to determine the hypoglycemic activities on different groups of alloxan induced diabetic rabbits. The complexes (1-6) were found better hypoglycemic agents as they stabilized the glucose level to about 175-105 mg dL-1 as compared to ligand P2HPA.

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STRUCTURE BASED DRUG DESIGNING, SCORING, AND SYNTHESIS OF SOME SUBSTITUTED SULPHONYLUREAS/GUANIDINE -BASED DERIVATIVES AS HYPOGLYCEMIC AGENTS

International Journal of Pharmacy and Pharmaceutical Sciences ◽

10.22159/ijpps.2017v9i12.21937 ◽

2017 ◽

Vol 9 (12) ◽

pp. 226 ◽

Cited By ~ 1

Author(s):

Ishan Panchal ◽

Dhrubo Jyoti Sen ◽

Archana Navle ◽

Umang Shah

Keyword(s):

Analytical Data ◽

Binding Pocket ◽

Docking Studies ◽

Diabetic Rats ◽

Hypoglycemic Activity ◽

Hypoglycemic Agents ◽

Reference Drug ◽

Glide Docking ◽

Docking Program

Objective: The present work deals with the designing, scoring, synthesis and, characterization of 1-(4-(2-(4-Substitutedphenylamino)-2-oxoethyl)phenylsulfonyl)-3-(4-substitutedbenzoyl)urea (5A-5B),1-(4-(2-(4-substitutedphenylamino)-2-oxoethyl)phenylsulfonyl)-3-(4-substituted-benzoyl)guanidine(5C-5E) and, 1-(4-Substitutedbenzoyl)-3-(4-(2-oxo-2-(piperazin-1-yl)ethyl)phenylsulfonyl)urea (5F-5H) based derivatives as hypoglycemic agents.Methods: Docking calculations were performed to predict the binding affinity between the AKR1C1 complexes and sulphonylureas compounds using the Glide docking program. Docking studies on LigPrep treated ligands were carried out to predict the binding pocket of protein 4YVP using the docking program. The QikProp program was used to predict the ADME/T properties of the analogues. All these newly synthesized compounds were screened for their in vivo hypoglycemic activity by most relevant animal models like alloxan-induced diabetic rats by measuring blood plasma concentration compared with reference drug glibenclamide.Results: Novel compounds 1-(4-(2-(4-Substitutedphenylamino)-2-oxoethyl)phenylsulfonyl)-3-(4-substitutedbenzoyl)urea (5A-5B), 1-(4-(2-(4-substitutedphenylamino)-2-oxoethyl)phenylsulfonyl)-3-(4-substitutedbenzoyl) guanidine (5C-5E), and 1-(4-Substitutedbenzoyl)-3-(4-(2-oxo-2-(piperazin-1-yl)ethyl)phenylsulfonyl)urea (5F-5H) were synthesised and characterized using spectral and analytical data. The results of molecular docking and in vivo hypoglycemic activity, all compounds have shown considerable activity with respect to glibenclimide, but compounds 5D (52.49±7.73) and 5E(48.18±4.22)are equipotent with respect to activity as compared to standard glibenclamide(55.97±3.19).Conclusion: Compounds 5D and 5E have exhibited good hypoglycemic activity,hence both the derivatives will consider as a lead molecule and further some modification in their structures to get a more potent anti-diabetic agent.

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Oxytocin analogues with non-coded amino acid residues in position 8: [8-Neopentylglycine]oxytocin and [8-cycloleucine]oxytocin

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19872317 ◽

1987 ◽

Vol 52 (9) ◽

pp. 2317-2325 ◽

Cited By ~ 5

Author(s):

Jan Hlaváček ◽

Jan Pospíšek ◽

Jiřina Slaninová ◽

Walter Y. Chan ◽

Victor J. Hruby

Keyword(s):

Amino Acid ◽

Solid Phase Synthesis ◽

Solid Phase ◽

The Other ◽

Amino Acid Residues ◽

Phase Synthesis ◽

Other Hand ◽

Fragment Condensation

[8-Neopentylglycine]oxytocin (II) and [8-cycloleucine]oxytocin (III) were prepared by a combination of solid-phase synthesis and fragment condensation. Both analogues exhibited decreased uterotonic potency in vitro, each being about 15-30% that of oxytocin. Analogue II also displayed similarly decreased uterotonic potency in vivo and galactogogic potency. On the other hand, analogue III exhibited almost the same potency as oxytocin in the uterotonic assay in vivo and in the galactogogic assay.

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Synthesis of Fragments of the Vasoactive Intestinal Peptide (VIP) and Analysis of Their Residual Biological Activities

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19951229 ◽

1995 ◽

Vol 60 (7) ◽

pp. 1229-1235 ◽

Cited By ~ 2

Author(s):

Ivana Zoulíková ◽

Ivan Svoboda ◽

Jiří Velek ◽

Václav Kašička ◽

Jiřina Slaninová ◽

...

Keyword(s):

Amino Acid ◽

Biological Activities ◽

Residual Activity ◽

Detailed Examination ◽

Amino Acid Residues ◽

Linear Peptide ◽

Zone Electrophoresis ◽

Capillary Zone

The vasoactive intestinal (poly)peptide (VIP) is a linear peptide containing 28 amino acid residues, whose primary structure indicates a low metabolic stability. The following VIP fragments, as potential metabolites, and their analogues were prepared by synthesis on a solid: [His(Dnp)1]VIP(1-10), VIP(11-14), [D-Arg12]VIP(11-14), [Lys(Pac)15,21,Arg20]VIP(15-22), and VIP(23-28). After purification, the peptides were characterized by amino acid analysis, mass spectrometry, RP HPLC, and capillary zone electrophoresis. In some tests, detailed examination of the biological activity of the substances in vivo and in vitro gave evidence of a low, residual activity of some fragments, viz. a depressoric activity in vivo for [His(Dnp)1]VIP(1-10) and a stimulating activity for the release of α-amylase in vitro and in vivo for [Lys(Pac)15,21,Arg20]VIP(15-22) and VIP(23-28).

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In VivoEffects of Leptin-Related Synthetic Peptides on Body Weight and Food Intake in Female ob/obMice: Localization of Leptin Activity to Domains Between Amino Acid Residues 106–140*

Endocrinology ◽

10.1210/endo.138.4.5087 ◽

1997 ◽

Vol 138 (4) ◽

pp. 1413-1418 ◽

Cited By ~ 42

Author(s):

Patricia Grasso ◽

Matthew C. Leinung ◽

Stacy P. Ingher ◽

Daniel W. Lee

Keyword(s):

Body Weight ◽

Weight Gain ◽

Amino Acid ◽

Food Intake ◽

Stop Codon ◽

Premature Stop Codon ◽

Amino Acid Residues ◽

Inactive Form ◽

In Vivo Effects

Abstract In C57BL/6J ob/ob mice, a single base mutation of the ob gene in codon 105 results in the replacement of arginine by a premature stop codon and production of a truncated inactive form of leptin. These observations suggest that leptin activity may be localized, at least in part, to domains distal to amino acid residue 104. To investigate this possibility, we synthesized six overlapping peptide amides corresponding to residues 106–167 of leptin, and examined their effects on body weight and food intake in female C57BL/6J ob/ob mice. When compared with vehicle-injected control mice, weight gain by mice receiving 28 daily 1-mg ip injections of LEP-(106–120), LEP-(116–130), or LEP-(126–140) was significantly (P < 0.01) reduced with no apparent toxicity. Weight gain by mice receiving LEP-(136–150), LEP-(146–160), or LEP-(156–167) was not significantly different from that of vehicle-injected control mice. The effects of LEP-(106–120), LEP-(116–130), or LEP-(126–140) were most pronounced during the first week of peptide treatment. Within 7 days, mice receiving these peptides lost 12.3%, 13.8%, and 9.8%, respectively, of their initial body weights. After 28 days, mice given vehicle alone, LEP-(136–150), LEP-(146–160), or LEP-(156–167) were 14.7%, 20.3%, 25.0%, and 24.8% heavier, respectively, than they were at the beginning of the study. Mice given LEP-(106–120) or LEP-(126–140) were only 1.8% and 4.2% heavier, respectively, whereas mice given LEP-(116–130) were 3.4% lighter. Food intake by mice receiving LEP-(106–120), LEP-(116–130), or LEP-(126–140), but not by mice receiving LEP-(136–150), LEP-(146–160), or LEP-(156–167), was reduced by 15%. The results of this study indicate 1) that leptin activity is localized, at least in part, in domains between residues 106–140; 2) that leptin-related peptides have in vivo effects similar to those of native leptin; and 3) offer hope for development of peptide analogs of leptin having potential application in human or veterinary medicine.

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A Potential Peptide From Soy Cheese Produced Using Lactobacillus delbrueckii WS4 for Effective Inhibition of SARS-CoV-2 Main Protease and S1 Glycoprotein

Frontiers in Molecular Biosciences ◽

10.3389/fmolb.2020.601753 ◽

2020 ◽

Vol 7 ◽

Author(s):

Rounak Chourasia ◽

Srichandan Padhi ◽

Loreni Chiring Phukon ◽

Md Minhajul Abedin ◽

Sudhir P. Singh ◽

...

Keyword(s):

Drug Targets ◽

Docking Studies ◽

Lactobacillus Delbrueckii ◽

Amino Acid Residues ◽

Main Protease ◽

Effective Inhibition ◽

Cheese Peptides ◽

Potential Inhibitors

The COVID-19 pandemic caused by novel SARS-CoV-2 has resulted in an unprecedented loss of lives and economy around the world. In this study, search for potential inhibitors against two of the best characterized SARS-CoV-2 drug targets: S1 glycoprotein receptor-binding domain (RBD) and main protease (3CLPro), was carried out using the soy cheese peptides. A total of 1,420 peptides identified from the cheese peptidome produced using Lactobacillus delbrueckii WS4 were screened for antiviral activity by employing the web tools, AVPpred, and meta-iAVP. Molecular docking studies of the selected peptides revealed one potential peptide “KFVPKQPNMIL” that demonstrated strong affinity toward significant amino acid residues responsible for the host cell entry (RBD) and multiplication (3CLpro) of SARS-CoV-2. The peptide was also assessed for its ability to interact with the critical residues of S1 RBD and 3CLpro of other β-coronaviruses. High binding affinity was observed toward critical amino acids of both the targeted proteins in SARS-CoV, MERS-CoV, and HCoV-HKU1. The binding energy of KFVPKQPNMIL against RBD and 3CLpro of the four viruses ranged from −8.45 to −26.8 kcal/mol and −15.22 to −22.85 kcal/mol, respectively. The findings conclude that cheese, produced by using Lb. delbrueckii WS4, could be explored as a prophylactic food for SARS-CoV-2 and related viruses. In addition, the multi-target inhibitor peptide, which effectively inhibited both the viral proteins, could further be used as a terminus a quo for the in vitro and in vivo function against SARS-CoV-2.

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The functional dyad of scorpion toxin Pi1 is not itself a prerequisite for toxin binding to the voltage-gated Kv1.2 potassium channels

Biochemical Journal ◽

10.1042/bj20030115 ◽

2004 ◽

Vol 377 (1) ◽

pp. 25-36 ◽

Cited By ~ 50

Author(s):

Stéphanie MOUHAT ◽

Amor MOSBAH ◽

Violeta VISAN ◽

Heike WULFF ◽

Muriel DELEPIERRE ◽

...

Keyword(s):

Amino Acid ◽

Scorpion Toxin ◽

Xenopus Laevis Oocytes ◽

Amino Acid Residues ◽

Voltage Gated ◽

Toxin Binding ◽

Ic50 Values

Pi1 is a 35-residue scorpion toxin cross-linked by four disulphide bridges that acts potently on both small-conductance Ca2+-activated (SK) and voltage-gated (Kv) K+ channel subtypes. Two approaches were used to investigate the relative contribution of the Pi1 functional dyad (Tyr-33 and Lys-24) to the toxin action: (i) the chemical synthesis of a [A24,A33]-Pi1 analogue, lacking the functional dyad, and (ii) the production of a Pi1 analogue that is phosphorylated on Tyr-33 (P-Pi1). According to molecular modelling, this phosphorylation is expected to selectively impact the two amino acid residues belonging to the functional dyad without altering the nature and three-dimensional positioning of other residues. P-Pi1 was directly produced by peptide synthesis to rule out any possibility of trace contamination by the unphosphorylated product. Both Pi1 analogues were compared with synthetic Pi1 for bioactivity. In vivo, [A24,A33]-Pi1 and P-Pi1 are lethal by intracerebroventricular injection in mice (LD50 values of 100 and 40 µg/mouse, respectively). In vitro, [A24,A33]-Pi1 and P-Pi1 compete with 125I-apamin for binding to SK channels of rat brain synaptosomes (IC50 values of 30 and 10 nM, respectively) and block rat voltage-gated Kv1.2 channels expressed in Xenopus laevis oocytes (IC50 values of 22 µM and 75 nM, respectively), whereas they are inactive on Kv1.1 or Kv1.3 channels at micromolar concentrations. Therefore, although both analogues are less active than Pi1 both in vivo and in vitro, the integrity of the Pi1 functional dyad does not appear to be a prerequisite for the recognition and binding of the toxin to the Kv1.2 channels, thereby highlighting the crucial role of other toxin residues with regard to Pi1 action on these channels. The computed simulations detailing the docking of Pi1 peptides on to the Kv1.2 channels support an unexpected key role of specific basic amino acid residues, which form a basic ring (Arg-5, Arg-12, Arg-28 and Lys-31 residues), in toxin binding.

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Role of Integrase in Reverse Transcription of the Saccharomyces cerevisiae Retrotransposon Ty1

Eukaryotic Cell ◽

10.1128/ec.4.6.1057-1065.2005 ◽

2005 ◽

Vol 4 (6) ◽

pp. 1057-1065 ◽

Cited By ~ 14

Author(s):

M. Wilhelm ◽

F.-X. Wilhelm

Keyword(s):

Saccharomyces Cerevisiae ◽

Amino Acid ◽

Specific Activity ◽

Rnase H ◽

Amino Acid Residues ◽

Acidic Amino Acid ◽

Acidic Domain ◽

Basic Region

ABSTRACT Reverse transcriptase (RT) with its associated RNase H (RH) domain and integrase (IN) are key enzymes encoded by retroviruses and retrotransposons. Several studies have implied a functional role of the interaction between IN and RT during the replication of retroviral and retrotransposon genomes. In this study, IN deletion mutants were used to investigate the role of IN on the RT activity of the yeast Saccharomyces cerevisiae retrotransposon Ty1. We have identified two domains of Ty1 integrase which have effects on RT activity in vivo. The deletion of a domain spanning amino acid residues 233 to 520 of IN increases the exogenous specific activity of RT up to 20-fold, whereas the removal of a region rich in acidic amino acid residues between residues 521 and 607 decreases its activity. The last result complements our observation that an active recombinant RT protein can be obtained if a small acidic tail mimicking the acidic domain of IN is fused to the RT-RH domain. We suggest that interaction between these acidic amino acid residues of IN and a basic region of RT could be critical for the correct folding of RT and for the formation of an active conformation of the enzyme.

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