Compound 27a Research Articles

Unique Azolyl Acylhydrazonyl Hybridization of Aloe Emodins to Access Potential Antibacterial Agents

Comprehensive SummaryA type of unique azole‐hybridized acylhydrazonyl aloe emodins (AAEs) were developed as new antibacterial agents for combating bacterial infections. Some target AAEs showed strong antibacterial activities, especially, tetrazolylthioether AAE 27a exhibited broad antibacterial spectrum with 16—256 folds and 8—64 folds more active antibacterial efficacy than the reference drugs aloe emodin and norfloxacin, respectively. Tetrazolylthioether AAE 27a also gave low hemolysis and cytotoxicity, as well as favorable bioavailability. Preliminary mechanism explorations revealed that tetrazolylthioether AAE 27a could cause bacterial membrane depolarization and damage the cell membrane, resulting in nucleic acid leakage. Moreover, compound 27a could intercalate into DNA to impede its replication and form supramolecular 27a‐DNA gyrase complex to disturb the function of DNA gyrase. These findings would provide valuable insights for the further exploration of azolyl acylhydrazonyl aloe emodins as new potential antibacterial candidates.

Discovery, Structure-Based Modification, In Vitro, In Vivo, and In Silico Exploration of m-Sulfamoyl Benzoamide Derivatives as Selective Butyrylcholinesterase Inhibitors for Treating Alzheimer's Disease.

For the potential therapy of Alzheimer's disease (AD), butyrylcholinesterase (BChE) has gradually gained worldwide interest in the progression of AD. This study used a pharmacophore-based virtual screening (VS) approach to identify Z32439948 as a new BChE inhibitor. Aiding by molecular docking and molecular dynamics, essential binding information was disclosed. Specifically, a subpocket was found and structure-guided design of a series of novel compounds was conducted. Derivatives were evaluated in vitro for cholinesterase inhibition and physicochemical properties (BBB, log P, and solubility). The investigation involved docking, molecular dynamics, enzyme kinetics, and surface plasmon resonance as well. The study highlighted compounds 27a (hBChE IC50 = 0.078 ± 0.03 μM) and (R)-37a (hBChE IC50 = 0.005 ± 0.001 μM) as the top-ranked BChE inhibitors. These compounds showed anti-inflammatory activity and no apparent cytotoxicity against the human neuroblastoma (SH-SY5Y) and mouse microglia (BV2) cell lines. The most active compounds exhibited the ability to improve cognition in both scopolamine- and Aβ1-42 peptide-induced cognitive deficit models. They can be promising lead compounds with potential implications for treating the late stage of AD.

Synthesis and biological evaluation of oleanolic acid derivatives with electrophilic warheads as antitumor agents.

Aim: The oleanolic acid derivatives containing electrophilic warheads were synthesized, and their antitumor activities were investigated. Materials & methods: The cytotoxicity of compounds against tumor cells were determined by theMTT method. The antitumor effects of compounds 27a, Y03 and Y04 were evaluated in vitro through a wound-healing assay, apoptosis and cell circle analysis, and cellular reactive oxide species determination. The levels of related proteins in MCF-7 cells treated with Y03 was determined through Western blot analysis. Results & conclusion: Compounds 27a, Y03 and Y04 displayed high cytotoxicity against breast cancer cells and inhibited cell migration, induced apoptosis, arrest cell circle at G0/G1 and promoted cellular reactive oxide species generation. The antitumor mechanism involved inhibition of Akt/mTOR and induction of ferroptosis.

Development of an Indole-Amide-Based Photoswitchable Cannabinoid Receptor Subtype 1 (CB1R) "Cis-On" Agonist.

Activation of the human cannabinoid receptor type 1 (hCB1R) with high spatiotemporal control is useful to study processes involved in different pathologies related to nociception, metabolic alterations, and neurological disorders. To synthesize new agonist ligands for hCB1R, we have designed different classes of photoswitchable molecules based on an indole core. The modifications made to the central core have allowed us to understand the molecular characteristics necessary to design an agonist with optimal pharmacological properties. Compound 27a shows high affinity for CB1R (Ki (cis-form) = 0.18 μM), with a marked difference in affinity with respect to its inactive "trans-off" form (CB1R Ki trans/cis ratio = 5.4). The novel compounds were evaluated by radioligand binding studies, receptor internalization, sensor receptor activation (GRABeCB2.0), Western blots for analysis of ERK1/2 activation, NanoBiT βarr2 recruitment, and calcium mobilization assays, respectively. The data show that the novel agonist 27a is a candidate for studying the optical modulation of cannabinoid receptors (CBRs), serving as a new molecular tool for investigating the involvement of hCB1R in disorders associated with the endocannabinoid system.

Discovery and development of a novel N-(3-bromophenyl)-{[(phenylcarbamoyl)amino]methyl}-N-hydroxythiophene-2-carboximidamide indoleamine 2,3-dioxygenase inhibitor using knowledge-based drug design

Indoleamine 2,3-dioxygenase-1 (IDO1) is a potential target for the next generation of cancer immunotherapies. We describe the development of two series of IDO1 inhibitors incorporating a N-hydroxy-thiophene-carboximidamide core generated by knowledge-based drug design. Structural modifications to improve the cellular activity and pharmacokinetic (PK) properties of the compounds synthesized, including extension of the side chain of the N-hydroxythiophene-2-carboximidamide core, resulted in compound 27a, a potent IDO1 inhibitor which demonstrated significant (51%) in vivo target inhibition on IDO1 in a human SK-OV-3 ovarian xenograft tumor mouse model. This strategy is expected to be applicable to the discovery of additional IDO1 inhibitors for the treatment of other diseases susceptible to modulation of IDO1.

Exploration of Long-Chain Vitamin E Metabolites for the Discovery of a Highly Potent, Orally Effective, and Metabolically Stable 5-LOX Inhibitor that Limits Inflammation.

Endogenous long-chain metabolites of vitamin E (LCMs) mediate immune functions by targeting 5-lipoxygenase (5-LOX) and increasing the systemic concentrations of resolvin E3, a specialized proresolving lipid mediator. SAR studies on semisynthesized analogues highlight α-amplexichromanol (27a), which allosterically inhibits 5-LOX, being considerably more potent than endogenous LCMs in human primary immune cells and blood. Other enzymes within lipid mediator biosynthesis were not substantially inhibited, except for microsomal prostaglandin E2 synthase-1. Compound 27a is metabolized by sulfation and β-oxidation in human liver-on-chips and exhibits superior metabolic stability in mice over LCMs. Pharmacokinetic studies show distribution of 27a from plasma to the inflamed peritoneal cavity and lung. In parallel, 5-LOX-derived leukotriene levels decrease, and the inflammatory reaction is suppressed in reconstructed human epidermis, murine peritonitis, and experimental asthma in mice. Our study highlights 27a as an orally active, LCM-inspired drug candidate that limits inflammation with superior potency and metabolic stability to the endogenous lead.

Design, synthesis, docking, ADMET studies, and anticancer evaluation of new 3-methylquinoxaline derivatives as VEGFR-2 inhibitors and apoptosis inducers

Vascular endothelial growth factor receptor-2 (VEGFR-2) plays a critical role in cancer angiogenesis. Inhibition of VEGFR-2 activity proved effective suppression of tumour propagation. Accordingly, two series of new 3-methylquinoxaline derivatives have been designed and synthesised as VEGFR-2 inhibitors. The synthesised derivatives were evaluated in vitro for their cytotoxic activities against MCF-7and HepG2 cell lines. In addition, the VEGFR-2 inhibitory activities of the target compounds were estimated to indicate the potential mechanism of their cytotoxicity. To a great extent, the results of VEGFR-2 inhibition were highly correlated with that of cytotoxicity. Compound 27a was the most potent VEGFR-2 inhibitor with IC50 of 3.2 nM very close to positive control sorafenib (IC50 = 3.12 nM). Such compound exhibited a strong cytotoxic effect against MCF-7 and HepG2, respectively with IC50 of 7.7 and 4.5 µM in comparison to sorafenib (IC50 = 3.51 and 2.17 µM). In addition, compounds 28, 30f, 30i, and 31b exhibited excellent VEGFR-2 inhibition activities (IC50 range from 4.2 to 6.1 nM) with promising cytotoxic activity. Cell cycle progression and apoptosis induction were investigated for the most active member 27a. Also, the effect of 27a on the level of caspase-3, caspase-9, and BAX/Bcl-2 ratio was determined. Molecular docking studies were implemented to interpret the binding mode of the target compounds with the VEGFR-2 pocket. Furthermore, toxicity and ADMET calculations were performed for the synthesised compounds to study their pharmacokinetic profiles

Design, synthesis and biological evaluation of hydroxypyridinone-coumarin hybrids as multimodal monoamine oxidase B inhibitors and iron chelates against Alzheimer's disease

A series of hybrids of hydroxypyridinone and coumarin were rationally designed, synthesized and biologically evaluated for their iron ion chelating and MAO-B inhibitory activities. Most of the compounds displayed excellent iron ion chelating effects and moderate to good anti-MAO-B activities. Compound 27a exhibited the most potent activity against MAO-B, with an IC50 value of 14.7 nM. Importantly, 27a showed good U251 cell protective effect and significantly ameliorated the cognitive dysfunction of scopolamine-induced AD mice. Moreover, molecular docking was performed to elucidate the probable ligand-receptor interaction, and the structure-activity relationships were also summarized.

A novel, potent, and orally bioavailable thiazole HCV NS5A inhibitor for the treatment of hepatitis C virus

A medicinal chemistry program based on the small-molecule HCV NS5A inhibitor daclatasvir has led to the discovery of dimeric phenylthiazole compound 8, a novel and potent HCV NS5A inhibitor. The subsequent SAR studies and optimization revealed that the cycloalkyl amide derivatives 27a-29a exhibited superior potency against GT1b with GT1b EC50 values at picomolar concentration. Interestingly, high diastereospecificity for HCV inhibition was observed in this class with the (1R,2S,1′R,2′S) diastereomer displaying the highest GT1b inhibitory activity. The best inhibitor 27a was found to be 3-fold more potent (GT1b EC50 = 0.003 nM) than daclatasvir (GT1b EC50 = 0.009 nM) against GT1b, and no detectable in vitro cytotoxicity was observed (CC50 > 50 μM). Pharmacokinetic studies demonstrated that compound 27a had an excellent pharmacokinetic profiles with a superior oral exposure and desired bioavailability after oral administration in both rats and dogs, and therefore it was selected as a developmental candidate for the treatment of HCV infection.

Design, synthesis and anti-tumor evaluation of novel steroidal glycoconjugate with furoxan derivatives

In this study, eighteen novel steroidal-furoxan derivatives with 3-glycosyl or 3-methoxy moiety (12a-c, 13a-c, 17a-c, 26a-c, 27a-c and 28a-c) were synthesized and their anti-proliferative activity was evaluated against eight drug-sensitive and three drug-resistant cancer cell lines HeLa, A2780, LNCaP, PC-3, MDA-MB-231, MCF-7, SW480, A549, MCF-7/ADR, A2780/CDDP and A2780/T. Most of them displayed significant anti-cancer potency in vitro with IC50 values at the nanomole level. Among them, 3-methoxy steroidal-furoxan hybrids expressed much better activity than that of 3-glycosyl substitute ones, while estrane and 5α-H-androstane scaffold were slightly more favorable to the improvement of anti-proliferative activity. Especially, compounds 27c and 28b showed the strongest cytotoxicity with IC50 values of 0.0007–0.034 and 0.0011–0.008 µM, respectively in five drug-sensitive cancer cell lines. Furthermore, 3-glycoconjugates 13a, 13c, 17b and 3-methoxy compounds 27a, 27c, 28b displayed lower toxicity in nontumorigenesis cells HOSEC and expressed a good selectivity against malignant cells in vitro. Preliminary study of pharmacology showed that the introduction of glucose at 3-position in steroidal core seems unable to use glucose transporters to improve the selectivity against proliferation of malignant cells, while the NO-releasing capacity might explain the potent anti-neoplastic activity of these compounds. And compound 28b could induce the apoptosis and hardly affected the cell cycle of A2780. Then, the further study of these steroidal-furoxan hybrids merits to explore and develop a desirable anti-cancer candidate.

Design, synthesis and characterization of potent microtubule inhibitors with dual anti-proliferative and anti-angiogenic activities

Microtubule has been an important target for anticancer drug development. Here we report the discovery and characterization of a series of fused 4-aryl-4H-chromene-based derivatives as highly potent microtubule inhibitors. Among a total of 37 derivatives synthesized, 23 exhibited strong in vitro anti-proliferative activities against A375 human melanoma cells. The relationship between the biological activities of these microtubule inhibitors and their chemical structure variations was analyzed. Studies of compounds 27a, 19a and 9a in parallel with colchicine as the positive control compound in a panel of biological assays revealed that these compounds blocked cell cycle progression, increased apoptosis, and inhibited HUVEC capillary tube formation at low nanomolar concentrations. The most potent compound 27a was also tested in eight additional cancer cell lines besides A375 cells and two non-cancer cells and showed potent and selective activity on these cancer cells. To understand the molecular and structure mechanism of action of these compounds, tubulin polymerization and molecular docking studies were carried out for 27a as the representative. The results were consistent with the mechanism by which 27a interacts with the colchicine binding site on tubulin and disrupts tubulin polymerization. With potent dual actions of microtubule destabilization and vascular disruption described above, this small molecule can serve as a valuable research probe of the function and role of microtubules in human diseases and promising lead for developing new therapeutic agents.

Discovery of N-substituted-endo-3-(8-aza-bicyclo[3.2.1]oct-3-yl)-phenol and -phenyl carboxamide series of μ-opioid receptor antagonists

Gastrointestinal dysfunction as a consequence of the use of opioid analgesics is of significant clinical concern. First generation drugs to treat these opioid-induced side-effects were limited by their negative impact on opioid receptor agonist-induced analgesia. Second generation therapies target a localized, peripherally-restricted, non-CNS penetrant drug distribution of opioid receptor antagonists. Herein we describe the discovery of the N-substituted-endo-3-(8-aza-bicyclo[3.2.1]oct-3-yl)-phenol and -phenyl carboxamide series of μ-opioid receptor antagonists. This report highlights the discovery of the key μ-opioid receptor antagonist pharmacophore and the optimization of in vitro metabolic stability through the application of a phenol bioisostere. The compounds 27a and 31a with the most attractive in vitro profile, formed the basis for the application of Theravance Biopharma’s multivalent approach to drug discovery to afford the clinical compound axelopran (TD-1211), targeted for the treatment of opioid-induced constipation.

ChemInform Abstract: Synthesis of 1-[cis-3-(Hydroxymethyl)cyclobutyl]-uracil, -thymine and -cytosine.

4-(Benzylsulfanyl)pyrimidin-2(1H)-one 6a is prepared from 1-benzoyluracil 10a in three steps and in satisfactory overall yield. Reproducible conditions are found for the cycloaddition reaction between allyl benzyl ether and dichloroketene, leading to the cyclobutanone derivative 17 in good yield. trans-3-(Benzyloxymethyl)cyclobutan-1-ol 15 reacts under standard Mitsunobu conditions with the pyrimidine derivative 6a on O-2 to give compound 20, which is converted into 2-[cis-3-(hydroxymethyl)-cyclobutoxy]pyrimidin-4(3H)-one 24 in good overall yield. Under the same Mitsunobu conditions, 3-benzoyluracil 11a and 3-benzoylthymine 11b react with the trans-alcohol 15 on N-1 to give their 1-[cis-3-(benzyloxymethyl)cyclobutyl] derivatives 27a and 27b, respectively. The latter compounds 27a and 27b are converted into 1-[cis-3-(hydroxymethyl)cyclobutyl]uracil 13a and 1-[cis-3-(hydroxymethyl)cyclobutyl]thymine 13b in satisfactory overall yields. The uracil derivative 13a is converted into 1-[cis-3-(hydroxymethyl)cyclobutyl]cytosine 14 in good yield.

Potent Antitumor 9-Anilinoacridines and Acridines Bearing an Alkylating N-Mustard Residue on the Acridine Chromophore: Synthesis and Biological Activity

A series of 9-anilinoacridine and acridine derivatives bearing an alkylating N-mustard residue at C4 of the acridine chromophore were synthesized. The N-mustard pharmacophore was linked to the C4 of the acridine ring with an O-ethyl (O-C(2)), O-propyl (O-C(3)), or O-butyl (O-C(4)) spacer. It revealed that all newly synthesized compounds were very potent cytotoxic agents against human leukemia and various solid tumors in vitro. These agents did not exhibit cross-resistance against vinblastine-resistant (CCRF-CEM/VBL) or taxol-resistant (CCRF-CEM/taxol) cells. It also showed that these agents were DNA cross-linking agents rather than topoisomerase II inhibitors. Of these agents, compounds 27a and 27c were shown to have potent antitumor activity in nude mice bearing the human breast carcinoma MX-1 xenograft. The therapeutic efficacies of these two agents are comparable to that of taxol.

Synthesis of 1-[cis-3-(hydroxymethyl)cyclobutyl]-uracil, -thymine and -cytosine

4-(Benzylsulfanyl)pyrimidin-2(1H)-one 6a is prepared from 1-benzoyluracil 10a in three steps and in satisfactory overall yield. Reproducible conditions are found for the cycloaddition reaction between allyl benzyl ether and dichloroketene, leading to the cyclobutanone derivative 17 in good yield. trans-3-(Benzyloxymethyl)cyclobutan-1-ol 15 reacts under standard Mitsunobu conditions with the pyrimidine derivative 6a on O-2 to give compound 20, which is converted into 2-[cis-3-(hydroxymethyl)-cyclobutoxy]pyrimidin-4(3H)-one 24 in good overall yield. Under the same Mitsunobu conditions, 3-benzoyluracil 11a and 3-benzoylthymine 11b react with the trans-alcohol 15 on N-1 to give their 1-[cis-3-(benzyloxymethyl)cyclobutyl] derivatives 27a and 27b, respectively. The latter compounds 27a and 27b are converted into 1-[cis-3-(hydroxymethyl)cyclobutyl]uracil 13a and 1-[cis-3-(hydroxymethyl)cyclobutyl]thymine 13b in satisfactory overall yields. The uracil derivative 13a is converted into 1-[cis-3-(hydroxymethyl)cyclobutyl]cytosine 14 in good yield.

Elektrophile Additionen an das Bicyclo[1.1.0]butan‐System von 1‐Phenyl‐ und 1‐(4‐Anisyl)tricyclo[4.1.0.02,7]heptan: Säure‐katalysierte Reaktionen mit Wasser und Methanol, Anlagerung von Essigsäure und Oxymercurierung

Electrophilic Additions to the Bicyclo[1.1.0]butane System of 1‐Phenyl‐ and 1‐(4‐Anisyl)tricyclo[4.1.0.02,7]heptane: Acid‐Catalyzed Reactions with Water and Methanol, Addition of Acetic Acid, and Oxymerucuration1‐(4‐Anisyl)tricyclo[4.1.0.02,7]heptane (37) was prepared from 1‐(4‐anisyl)cyclohexene, tetrabromomethane, and methyllithium in a one‐pot reaction. Starting from 37 and the analogous phenyl compound 19, the oxymercuration/demercuration sequence provided the exo‐6‐aryl‐endo‐6‐norpinanols 30a and 20a, respectively. By reaction with triphenyl‐stannane, the bromo compound 27a was converted into endo‐6‐phenyl‐exo‐6‐norpinanol 28a. Treatment of 19 with aqueous sulfuric acid led to a mixture of the alcohols 20a–25a. Mixtures of a very similar composition were obtained on hydrolysis of the 3,5‐dinitrobenzoates 20b and 28b of 20a and 28a in 80% aqueous acetone. Kinetic measurements revealed the same rate for the hydrolysis of 20b and 28b. The proof of the presence of 20a among the products of the reactions of 19, 20b, and 28b showed the intermediacy of an unrearranged cation, to which the classical structure 16 is ascribed. That acetic acid is too weak a nucleophile to intercept 16 follows from the structure of the adducts to 19. All of them (21b, 22b, 25b, 26b) have rearranged skeletons. In contrast, the stronger nucleophile methanol trapped 16 more efficiently than water to give the diastereomeric 6‐norpinyl methyl ethers 20d and 28d. The reaction of 37 with acetic acid and 10−4 M hydrochloric acid as well as the hydrolysis the 3,5‐dinitrobenzoate 30c of 30a produced mainly the diastereomeric 6‐norpinyl acetates 30b and 31b and 6‐norpinanols 30a and 31a, respectively. Whereas the protonation of 19 and 37 gives the classical cations 16 and 17, respectively, the oxymercuration of these substrates results in the generation of the nonclassical cations 44 and 46. This was concluded from the configuration of the demercuration products 20a and 30a and the absence of the diastereomers 28a and 31a.

Synthesis of 5,6-dideoxy-3- O-methyl-5- C-(phenylphosphinyl)- d-glucopyranose and its 1,2,4-triacetate

Methyl phenylphosphonite or dimethyl phosphite underwent acid-catalyzed addition reactions with some hexofuranos-5-ulose 5-( p-tolylsulfonylhydrazones) ( 7, 9, and 16), to give the corresponding adducts, 17, 18, 19, and 21. The isomer ratios of the adducts were affected by a 3-substituent in the hydrazones. Treatment of adduct 21 with sodium borohydride and sodium dihydrobis(2-methoxyethoxy)-aluminate (SDMA), followed by acid hydrolysis, gave 5,6-dideoxy-3- O-methyl-5- C-(phenylphosphinyl)- d-glucopyranose ( 26), which was acetylated to give the 1,2,4-tri- O-acetyl derivatives 27a and 27b. Conformational analysis of compound 27a by X-ray crystallography revealed that the compound was 1,2,4-tri- O-acetyl-5,6-dideoxy-3- O-methyl-5- C-[( S)-phenylphosphinyl]-β- d-glucopyranose in the 4 C 1( d) form having all substituents equatorial.