Nonpeptidic angiotensin II AT1 receptor antagonists derived from 6-substituted aminocarbonyl and acylamino benzimidazoles

Design, Synthesis, and Biological Evaluation of New Oxadiazole Derivatives as Efficient Antihypertension Drugs

A series of novel oxadiazole derivatives were designed, synthesized, and evaluated for their pharmacological effects. All target compounds were subjected to analysis using 1H NMR, 13C NMR, and mass spectrometry. They showed a strong affinity to the AT1 receptor and effectively lowered blood pressure in spontaneously hypertensive rats at a nanomolar level. Compounds IV1 and IV2 were particularly effective, demonstrating comparable or greater potency in reducing blood pressure compared to Losartan. Therefore, compounds IV1 and IV2 have the potential to be developed as antihypertension medications.

In Silico Based Structural and Fingerprint Analysis of Structurally Diverse AT1 inhibitors

Background and Objective:

The development of pharmacologically active molecules for the treatment of hypertension and other cardiovascular diseases are important nowadays. In the present investigation, computational techniques have been implemented on Angiotensin II Type 1 (AT1) antagonists to develop better predictive models.

Methods:

Quantitative Structure Activity Relationship (QSAR) and structural patterns/fragments analyses were performed using physicochemical descriptors and MACCS Fingerprints calculaced from AT1 inhibitors collected from the literature.

Results:

The significant models developed have been validated by Leave One Out (LOO) and test set methods, which exhibit considerable Q2 values (>0.65 for the training set and >0.5 for the test set) and the R2pred values for the models are also >0.5. The applicability of the contributed descriptors in these models revealed that the chlorine atom, dipole moment, hydrogen bond donor atoms and electrostatic potential are negatively contributing, and the presence of bond between heavy atoms and the carbon atom connected with small side chain and topological polar vdW surface area are favorable for the AT1 antagonistic activity. The MACCS Fingerprints showed that the presence of atoms (kind of heavy atoms), such as N, O, and S, connected with other heteroatoms or carbon or any other atoms, through single or double bonds are predominantly present in highly active molecules. The presence of halogens, long chain alkanes, halogenated alkanes, and sulfur atoms attached with nitrogen through any atoms are responsible for decreased AT1 antagonistic activity.

Conclusion:

The results have provided additional information on the structural patterns of the compounds based on its MACCS Fingerprints, which may be used for further characterization and design of novel AT1 inhibitors.

Design, synthesis and biological evaluation of novel fluoro-substituted benzimidazole derivatives with anti-hypertension activities

A series of new fluoro-substituted benzimidazole derivatives were designed, synthesized and pharmacologically evaluated. All the target compounds were characterized by ¹HNMR, ¹³CNMR, mass spectra and elemental analysis. The biological evaluation showed that most of the synthesized compounds displayed nanomolar affinity to the angiotensin II type 1 (AT₁) receptor and could decrease blood pressure efficiently in spontaneously hypertensive rats. The maximal response of mean blood pressure (MBP) lowered 74.5 ± 3.5 mmHg (1g) and 69.2 ± 0.9 mmHg (2a) at 10 g/kg after oral administration, and the antihypertensive effect lasted beyond 24 h, which performed better than both losartan and telmisartan. So, compounds 1g and 2a may be considered as potential antihypertension drug candidates.

Design, synthesis and biological evaluation of AT1 receptor blockers derived from 6-substituted aminocarbonyl benzimidazoles

A series of new 6-substituted aminocarbonyl benzimidazole derivatives with 1, 4-disubsituted or 1, 5-disubsituted indole moiety and benzoic acid moiety were designed, synthesized and pharmacologically evaluated. Most of the synthesized compounds could bind to the AT₁ receptor and decrease blood pressure significantly. Notably, 2e and 1h could obviously decrease MBP in a dose dependent manner. The maximal response lowered 57.9 ± 2.3 mmHg (2e) and 57.6 ± 1.9 mmHg (1h) of MBP at 10 mg/kg after oral administration, and the antihypertensive effect lasted beyond 24 h, which performed better than Losartan (Fig. 1). These results indicate that 2e and 1h are effective and long-lasting anti-hypertension drug candidates and deserve further investigation for therapeutic application.

Design, Synthesis, and Biological Evaluation of 6-Benzoxazole Benzimidazole Derivatives with Antihypertension Activities

A series of new angiotensin II receptor 1 antagonists were prepared. They displayed nanomolar affinity to AT₁ receptor and could decrease blood pressure efficiently in spontaneously hypertensive rats. Among them, compounds 1b and 2b could reduce the blood pressure with more or equal potency compared to Losartan. So, compounds 1b and 2b could be considered as potential antihypertension drug candidates.

Integration of multi-scale molecular modeling approaches with experiments for the in silico guided design and discovery of novel hERG-Neutral antihypertensive oxazalone and imidazolone derivatives and analysis of their potential restrictive effects on cell proliferation

AT1 antagonists is the most recent drug class of molecules against hypertension and they mediate their actions through blocking detrimental effects of angiotensin II (A-II) when acts on type I (AT1) A-II receptor. The effects of AT1 antagonists are not limited to cardiovascular diseases. AT1 receptor blockers may be used as potential anti-cancer agents - due to the inhibition of cell proliferation stimulated by A-II. Therefore, AT1 receptors and the A-II biosynthesis mechanisms are targets for the development of new synthetic drugs and therapeutic treatment of various cardiovascular and other diseases. In this work, multi-scale molecular modeling approaches were performed and it is found that oxazolone and imidazolone derivatives reveal similar/better interaction energy profiles compared to the FDA approved sartan molecules at the binding site of the AT1 receptor. In silico-guided designed hit molecules were then synthesized and tested for their binding affinities to human AT1 receptor in radioligand binding studies, using [¹²⁵I-Sar¹-Ile⁸] AngII. Among the compounds tested, 19d and 9j molecules bound to receptor in a dose response manner and with relatively high affinities. Next, cytotoxicity and wound healing assays were performed for these hit molecules. Since hit molecule 19d led to deceleration of cell motility in all three cell lines (NIH3T3, A549, and H358) tested in this study, this molecule is investigated in further tests. In two cell lines (HUVEC and MCF-7) tested, 19d induced G2/M cell cycle arrest in a concentration dependent manner. Adherent cells detached from the plates and underwent cell death possibly due to apoptosis at 19d concentrations that induced cell cycle arrest.

Design, synthesis and evaluation of novel angiotensin II receptor 1 antagonists with antihypertensive activities

A novel Ang II receptor 1 antagonist 1f was found to be an efficient, long-acting and safe antihypertensive drug candidate.

Therapeutic evolution of benzimidazole derivatives in the last quinquennial period

Benzimidazole, a fused heterocycle bearing benzene and imidazole has gained considerable attention in the field of contemporary medicinal chemistry. The moiety is of substantial importance because of its wide array of pharmacological activities. This nitrogen containing heterocycle is a part of a number of therapeutically used agents. Moreover, a number of patents concerning this moiety in the last few years further highlight its worth. The present review covers the recent work published by scientists across the globe during last five years.

Dietary peptides from the non-digestible fraction of Phaseolus vulgaris L. decrease angiotensin II-dependent proliferation in HCT116 human colorectal cancer cells through the blockade of the renin–angiotensin system

Peptides in common beans reduced angiotensin II-dependent proliferation in HCT116 colon cancer cells.

Synthesis of Several New 2-Substituted Benzimidazoles

A series of new 2-substituted ethyl-4-methyl-1 H-benzimidazole-6-carboxylates has been synthesised and one X-ray crystal structure determined that the synthetic method is reliable.

Rational drug design and synthesis of molecules targeting the angiotensin II type 1 and type 2 receptors

The angiotensin II (Ang II) type 1 and type 2 receptors (AT1R and AT2R) orchestrate an array of biological processes that regulate human health. Aberrant function of these receptors triggers pathophysiological responses that can ultimately lead to death. Therefore, it is important to design and synthesize compounds that affect beneficially these two receptors. Cardiovascular disease, which is attributed to the overactivation of the vasoactive peptide hormone Αng II, can now be treated with commercial AT1R antagonists. Herein, recent achievements in rational drug design and synthesis of molecules acting on the two AT receptors are reviewed. Quantitative structure activity relationships (QSAR) and molecular modeling on the two receptors aim to assist the search for new active compounds. As AT1R and AT2R are GPCRs and drug action is localized in the transmembrane region the role of membrane bilayers is exploited. The future perspectives in this field are outlined. Tremendous progress in the field is expected if the two receptors are crystallized, as this will assist the structure based screening of the chemical space and lead to new potent therapeutic agents in cardiovascular and other diseases.

Design, synthesis and biological activity of 4′-[(benzimidazol-1-yl)methyl]biphenyl-2-sulphonamides as dual angiotensin II and endothelin A receptor antagonists

A series of novel 4′-[(benzimidazol-1-yl)methyl]biphenyl-2-sulphonamides was designed, and their molecular model simulation fitting to a new HipHop 3D pharmacophore model was examined.

Synthesis and biological evaluation of 4′-[(benzimidazol-1-yl) methyl]biphenyl-2-amides as dual angiotensin II and endothelin A receptor antagonists

Discovery of new benzimidazoles as potent dual AT₁ and ET_A receptor antagonists with the novel N-(1H-tetrazol-5-yl)-amide fragment.

Comprehensive Review in Current Developments of Benzimidazole-Based Medicinal Chemistry

The properties of benzimidazole and its derivatives have been studied over more than one hundred years. Benzimidazole derivatives are useful intermediates/subunits for the development of molecules of pharmaceutical or biological interest. Substituted benzimidazole derivatives have found applications in diverse therapeutic areas such as antiulcer, anticancer agents, and anthelmintic species to name just a few. This work systematically gives a comprehensive review in current developments of benzimidazole-based compounds in the whole range of medicinal chemistry as anticancer, antibacterial, antifungal, anti-inflammatory, analgesic agents, anti-HIV, antioxidant, anticonvulsant, antitubercular, antidiabetic, antileishmanial, antihistaminic, antimalarial agents, and other medicinal agents. This review will further be helpful for the researcher on the basis of substitution pattern around the nucleus with an aim to help medicinal chemists for developing an SAR on benzimidazole drugs/compounds.