Current Targets and Future Directions of Positive Inotropes for Heart Failure.

While a congestive heart failure patient will ultimately need an assist device or even a replacement heart as the disease progresses, not every patient is qualified for such advanced therapy. Such patients awaiting better circulatory support benefit from positive inotropes in the meantime as palliative care. These agents are often prescribed in patients with acute decompensated heart failure, with reduced left ventricular ejection fraction and symptoms of organ dysfunction.

Nitroimidazopyrazinones with Oral Activity against Tuberculosis and Chagas Disease in Mouse Models of Infection.

Tuberculosis and parasitic infections continue to impose a significant threat to global public health and economic growth. There is an urgent need to develop new treatments to combat these diseases. Here, we report the and profiles of a new bicyclic nitroimidazole subclass, namely, nitroimidazopyrazinones, against mycobacteria and .

Modern vaccine development via reverse vaccinology to combat antimicrobial resistance.

With the continuous evolution of bacteria, the global antimicrobial resistance health threat is causing millions of deaths yearly. While depending on antibiotics as a primary treatment has its merits, there are no effective alternatives thus far in the pharmaceutical market against some drug-resistant bacteria. In recent years, vaccinology has become a key topic in scientific research.

Mesoporous Silica Nanoparticles Improve Oral Delivery of Antitubercular Bicyclic Nitroimidazoles.

Pretomanid and MCC7433, a novel nitroimidazopyrazinone analog, are promising antitubercular agents that belong to the bicyclic nitroimidazole family. Despite possessing high cell permeability, they suffer from poor aqueous solubility and require specialized formulations in order to be orally bioavailable. To address this limitation, we investigated the use of mesoporous silica nanoparticles (MCM-41) as drug carriers.

A rhodamine based chemosensor for solvent dependent chromogenic sensing of cobalt (II) and copper (II) ions with good selectivity and sensitivity: Synthesis, filter paper test strip, DFT calculations and cytotoxicity.

A new chemosensor 1 was synthesized by reacting rhodamine B hydrazide and 2,3,4-trihydroxybenzaldehyde, which was then characterized by spectroscopic techniques and single crystal X-ray crystallography. Sensor 1 has the ability to sense Co/Cu ions by "naked-eye" with an apparent colour change from colourless to pink in different solvent system, MeCN and DMF respectively. Furthermore, it can selectively detect Co/Cu among wide range of different metal ions, and it exhibits low detection limit of 4.

Antitubercular and Antiparasitic 2-Nitroimidazopyrazinones with Improved Potency and Solubility.

Following the approval of delamanid and pretomanid as new drugs to treat drug-resistant tuberculosis, there is now a renewed interest in bicyclic nitroimidazole scaffolds as a source of therapeutics against infectious diseases. We recently described a nitroimidazopyrazinone bicyclic subclass with promising antitubercular and antiparasitic activity, prompting additional efforts to generate analogs with improved solubility and enhanced potency. The key pendant aryl substituent was modified by (i) introducing polar functionality to the methylene linker, (ii) replacing the terminal phenyl group with less lipophilic heterocycles, or (iii) generating extended biaryl side chains.

Design, Synthesis, and Biological Evaluation of 2-Nitroimidazopyrazin-one/-es with Antitubercular and Antiparasitic Activity.

Tuberculosis and parasitic diseases, such as giardiasis, amebiasis, leishmaniasis, and trypanosomiasis, all urgently require improved treatment options. Recently, it has been shown that antitubercular bicyclic nitroimidazoles such as pretomanid and delamanid have potential as repurposed therapeutics for the treatment of visceral leishmaniasis. Here, we show that pretomanid also possesses potent activity against Giardia lamblia and Entamoeba histolytica, thus expanding the therapeutic potential of nitroimidazooxazines.

Nitroimidazoles: Molecular Fireworks That Combat a Broad Spectrum of Infectious Diseases.

Infectious diseases claim millions of lives every year, but with the advent of drug resistance, therapeutic options to treat infections are inadequate. There is now an urgent need to develop new and effective treatments. Nitroimidazoles are a class of antimicrobial drugs that have remarkable broad spectrum activity against parasites, mycobacteria, and anaerobic Gram-positive and Gram-negative bacteria.

Ethyl nitrobenzoate: A novel scaffold for cholinesterase inhibition.

A series of novel cholinesterase inhibitors containing nitrobenzoate core structure were synthesized by a facile and efficient method. The structure of the novel compounds were fully characterized and confirmed by analytical as well as spectroscopic methods. Compound indicated as 2f was found to possess the best cholinesterase inhibitory activities of all the evaluated compounds.

Synthesis and evaluation of antimycobacterial activity of new benzimidazole aminoesters.

A total of 51 novel benzimidazoles were synthesized by a 4-step reaction starting from basic compound 4-fluoro-3-nitrobenzoic acid under relatively mild reaction conditions. The structure of the novel benzimidazoles was confirmed by mass spectra as well as (1)H NMR spectroscopic data. Out of the 51 novel synthesized compounds, 42 of them were screened for their antimycobacterial activity against Mycobacterium tuberculosis H37Rv strain using BacTiter-Glo™ Microbial Cell Viability (BTG) method.

Benzimidazoles as new scaffold of sirtuin inhibitors: green synthesis, in vitro studies, molecular docking analysis and evaluation of their anti-cancer properties.

Two series of novel benzimidazole derivatives were designed, synthesized and evaluated for their SIRT1 and SIRT2 inhibitory activity. Among the newly synthesized compounds, compound 4j displayed the best inhibitory activity for SIRT1 (IC50 = 54.21 μM) as well as for SIRT2 (IC50 = 26.

Synthesis and evaluation of novel benzimidazole derivatives as sirtuin inhibitors with antitumor activities.

A total of 15 novel benzimidazole derivatives were designed, synthesized and evaluated for their SIRT1 and SIRT2 inhibitory activity. All compounds showed better inhibition on SIRT2 as compared to SIRT1. Among these, compound 5j displayed the best inhibitory activity for SIRT1 (IC50=58.

Antituberculosis: synthesis and antimycobacterial activity of novel benzimidazole derivatives.

A total of seven novel benzimidazoles were synthesized by a 4-step reaction starting from 4-fluoro-3-nitrobenzoic acid under relatively mild reaction conditions. The synthesized compounds were screened for their antimycobacterial activity against M. tuberculosis H₃₇Rv (MTB-H₃₇Rv) and INH-resistant M.

Synthesis, characterization, and molecular docking analysis of novel benzimidazole derivatives as cholinesterase inhibitors.

Two series of novel acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitors containing benzimidazole core structure were synthesized by a four-step reaction pathway starting from 4-fluoro-3-nitrobenzoic acid as the basic compound. The structure of the novel benzimidazoles was characterized and confirmed by the elemental and mass spectral analyses as well as (1)H NMR spectroscopic data. Of the 34 novel synthesized compounds, three benzimidazoles revealed AChE inhibition with IC50<10 μM.

A facile three-component [3+2]-cycloaddition for the regioselective synthesis of highly functionalised dispiropyrrolidines acting as antimycobacterial agents.

A series of fourteen dispiropyrrolidines were synthesized using [3+2]-cycloaddition reactions and were screened for their antimycobacterial activity against Mycobacterium tuberculosis H(37)Rv in HTS (High Throughput Screen). Most of the compounds showed moderate to good activity with MIC of less than 20 μM. Compound 4'-(4-bromophenyl)-1'-methyldispiro[acenaphthylene-1,2'-pyrrolidine-3',2″-indane]-2,1″(1H)-dione (4c) was found to be the most active with MIC of 12.

4'-(3-Bromo-phen-yl)-1'-methyl-dispiro-[indan-2,2'-pyrrolidine-3',2''-indan]-1,3,1''-trione.

In the title compound, C(27)H(20)BrNO(3), two intra-molecular C-H⋯O hydrogen bonds both form S(6) rings. The pyrrolidine ring adopts a twisted conformation about the C-C bond bearing the indane ring systems. The other two five-membered rings within the indane systems are in shallow envelope conformations, with the spiro C atoms as the flap atoms.

Antimycobacterial activity: a facile three-component [3+2]-cycloaddition for the regioselective synthesis of highly functionalised dispiropyrrolidines.

A series of twelve dispiropyrrolidines were synthesized using [3+2]-cycloaddition reactions. The synthesized compounds were screened for their antimycobacterial activity against M. tuberculosis H(37)Rv and INH resistant M.

7'-Phenyl-1',3',5',6',7',7a'-hexa-hydro-dipiro[acenaphthyl-ene-1,5'-pyrrolo-[1,2-c]thia-zole-6',2''-indane]-2,1''(1H)-dione.

In the title compound, C(31)H(23)NO(2)S, the pyrrolidine ring adopts an envelope conformation (with the spiro C atom as the flap), while the thia-zolidine ring and the two cyclo-pentane rings adopt twisted conformations. The mean plane through the hexa-hydro-pyrrolo-[1,2-c]thia-zole ring [r.m.

4'-(4-Bromo-phen-yl)-1'-methyl-dispiro-[acenaphthyl-ene-1,2'-pyrrolidine-3',2''-indane]-2,1''(1H)-dione.

In the title compound, C(30)H(22)BrNO(2), the cyclo-pentane ring of the dihydro-acenaphthyl-ene group and the pyrrolidine ring are both in envelope conformations with the spiro C atom and N atom, respectively, as the flap atom. The cyclo-pentane ring of the indane group adopts a half-chair conformation. A weak intra-molecular C-H⋯O hydrogen bond forms an S(8) ring motif.

1'-Methyl-4'-[4-(trifluoro-meth-yl)phen-yl]dispiro-[acenaphthyl-ene-1,2'-pyrrolidine-3',2''-indane]-2,1''(1H)-dione.

In the title compound, C(31)H(22)F(3)NO(2), the pyrrolidine and cyclo-pentane rings within the dihydro-indene ring system are in envelope conformations, with the N atom and the spiro-C atom at the flap, respectively. An intra-molecular C-H⋯O hydrogen bond forms an S(8) ring motif. The mean plane through the pyrrolidine ring [r.

7'-(2,5-Dimeth-oxy-phen-yl)-1',3',5',6',7',7a'-hexa-hydro-dispiro-[indan-2,5'-pyrrolo-[1,2-c][1,3]thia-zole-6',2''-indan]-1,3,1''-trione.

In the title compound, C(30)H(25)NO(5)S, all the five-membered rings are in envelope conformations with the spiro and methylene C atoms as the flap atoms. Intra-molecular C-H⋯O inter-actions stabilize the mol-ecular structure and form S(6) and S(7) ring motifs. The mean plane through the hexa-hydro-pyrrolo-[1,2-c]thia-zole ring [r.

(E)-2-[4-(Trifluoro-meth-yl)benzyl-idene]-2,3-dihydro-1H-inden-1-one.

In the title mol-ecule, C(17)H(11)F(3)O, the indan ring system and the trifluoro-methyl-substituted benzene ring are approximately individually planar and form a dihedral angle of 1.81 (5)° with each other. In the crystal, mol-ecules are linked by pairs of weak bifurcated (C-H)(2)⋯O hydrogen bonds to form centrosymmetric dimers, generating R(2) (1)(6) and R(2) (2)(10) ring motifs.

Ethyl 2-(1,3-benzodioxol-5-yl)-1-[3-(2-oxopyrrolidin-1-yl)prop-yl]-1H-benz-imidazole-5-carboxyl-ate.

In the title compound, C(24)H(25)N(3)O(5), the benzimidazole and benzodioxole ring systems are each approximately planar [maximum deviations = 0.043 (1) and 0.036 (1) Å, respectively].

1'-Methyl-4'-[4-(trifluoro-meth-yl)phen-yl]dispiro-[indan-2,2'-pyrrolidine-3',2''-indan]-1,3,1''-trione.

In the title compound, C(28)H(20)F(3)NO(3), the pyrrolidine ring adopts a half-chair conformation. The other five-membered rings adopt envelope conformations with the spiro and methylene C atoms as the flap atoms. In the crystal, mol-ecules are connected via weak C-H⋯O hydrogen bonds, forming sheets parallel to the bc plane.

4'-(4-Bromo-phen-yl)-1'-methyl-dispiro-[indan-2,2'-pyrrolidine-3',2''-indan]-1,3,1''-trione.

In the title compound, C(27)H(20)BrNO(3), the pyrrolidine ring adopts a half-chair conformation, while the other five-membered rings adopt flattened envelope conformations with the spiro C atoms as the flap atoms. An intra-molecular C-H⋯O hydrogen bond occurs, generating an S(6) ring. In the crystal, mol-ecules are connected via weak C-H⋯O hydrogen bonds, forming chains along the c axis.