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New N-heterocylic, homocyclic and aliphatic dronic acids were synthesized through an improved facile and versatile route by the reaction of various carboxylic acids with Phosphorus trichloride (PC), phosphorus acid (PA) and methanesulfonic acid under reflux and inert atmosphere. Representatively, the dronic acid derived from stearic acid as a long chained fatty acid was also synthesized. All the obtained compounds were analyzed and characterized by means of FT IR, 1H, 13C and 31P NMR spectroscopic techniques. In addition, the compound derived from stearic acid was characterized by means of FT IR and Mass spectrometry due to its insolubility in D2O and DMSO-d6. [ABSTRACT FROM AUTHOR]

A simple and effective approach for the preparation of 1,2,3-triazolyl-based metronidazole hybrid analogues as promising anti-Leishmania agents using [CuL-SiO-HA] as a catalyst is described. The catalyst was fully characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission, thermogravimetric analysis (TGA), energy-dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FT-IR), and inductively coupled plasma (ICP) analysis. Exploiting this non-toxic and mild catalyst provides good to excellent yields of final products with reactive pharmacophores. All compounds were assessed against Leishmania major, and it was determined that 16k and 16j were the most potent compounds with IC50 values of 7.5 mM and 8.1 mM compared to metronidazole as a reference drug, respectively. Furthermore, molecular docking studies were carried out to determine the detailed binding modes and critical interactions with the target protein. The drug likeness and in silico ADMET for all compounds were predicted. The computational results illustrated desirable matches with anti-Leishmania activity, and in this regard, 16k and 16j can be considered as future drug candidates against Leishmania. [ABSTRACT FROM AUTHOR]

The design, synthesis and biological evaluation of some aryloxy propanol amino acid derivatives have been described. Synthetic pathways is consisted of the reaction of phenol derivatives with epichlorohydrin and/or epibromohydrin produced the various O‐phenol ether adducts. In continue, the reaction of amino acid with O‐phenol ether adducts generated the new class of β‐blocking agents. The products were evaluated for their cardiovascular property. The 2‐kidney‐1‐clip method was used to induce renovascular hypertension in rats. New analogues of propranolol were evaluated in order to find the most appropriate ones for reducing the hypertension. Our results showed that compound 4 d [i. e.: (2‐hydroxy‐3‐phenoxypropyl) glycine] was effective in blood pressure lowering, even lower than propranolol as a standard drug. All the modelling study was performed at physiological pH (pH∼7.0–7.4).The MEP and docking analysis have shown the appropriate fitting of (2‐hydroxy‐3‐phenoxypropyl) glycine in human β2‐adrenergic receptor active site. [ABSTRACT FROM AUTHOR]

A green and highly efficient approach for the synthesis of 3,4-dihydropyrimidine-2(1H)-one/thione derivatives is described. In this approach, the three-component Biginelli reaction between (thio)urea, methyl acetoacetate and aldehydes under solvent-free condition in the presence of chitosan-silica sulfate nano hybrid (CSSNH) as a green and heterogeneous nano catalyst affords the corresponding products in good to excellent yields and in short reaction times. CSSNH is a cheap, eco-friendly, and non-toxic nano catalyst that could be easily prepared, handled, and reused for many reaction runs without significant loss of its activity. [ABSTRACT FROM AUTHOR]

Substituted imidazoles have wild applications in different area of sciences and industries. In this research, the catalytic activity of PPh3 as a cheap and efficient organocatalyst is reported for synthesis of 2,4,5‐trisubstituted imidazoles. In this method, ultrasonic assisted one‐pot, three‐component reaction of benzil, aldehydes, urea and PPh3 in ethylene glycol as a green solvent at room temperature has been achieved to afford the structurally diverse 2,4,5‐trisubstituted imidazoles in 80–95 %. The effect of different parameters on the reaction progress was also discussed. Utilizing ultrasonic irradiation dramatically improved the reaction in terms of yields and reaction times compared to conventional heating technique. The current protocol offers many advantages such as mild reaction conditions, short reaction time, the use of non‐metallic, harmless, and cheap catalyst, ease of separation and purification, simple work‐up procedure, and the reactivity to all types of aldehydes particularly the aliphatic aldehydes. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of chitosan-silica sulfate nano hybrid ( CSSNH) as a novel and efficient heterogeneous nano catalyst involving acid-base bifunctional activity is described. The catalytic potency and activity of this eco-friendly catalyst was investigated in regioselective ring opening of epoxides with carboxylic acids to access structurally diverse 1,2-diol mono-esters in good to excellent yields. CSSNH catalyst was characterized using different microscopic and spectroscopic techniques encompassing scanning electron microscopy, transmission electron microscopy, X-ray diffraction, N2 adsorption isotherm, and Fourier transform infrared spectroscopy. The green nature, cheapness, efficiency, ease of preparation, handling and reusability of this new catalyst makes this catalyst to be useful for green industrial processes. [ABSTRACT FROM AUTHOR]

A simple and straightforward one-pot three-component synthesis of 2 H-indazoles through copper-catalyzed consecutive condensation, C-N and N-N bond formations of easily accessible starting materials under ligand-free conditions is described. In this protocol, treatment of substituted 2-bromobenzaldehydes, structurally diverse amines, and [bmim]N3 in the presence of Cu/aminoclay/reduced graphene oxide nanohybrid (Cu/AC/r-GO nanohybrid) as an efficient heterogeneous catalyst affords the corresponding 2 H-indazoles in good to excellent yields. The influence of effective parameters on the efficient progress of the reaction was studied. The Cu/AC/r-GO nanohybrid is a stable and inexpensive catalyst that could be simply prepared, recovered, and reused for several reaction runs with no significant decrease in its reactivity. [ABSTRACT FROM AUTHOR]

Dengue virus (DENV) from the Flaviviridae family causes an epidemic disease that seriously threatens human life. The viral serine protease NS2B-NS3 is a promising target for drug development against DENV and other flaviviruses. We here report the design, synthesis, and in-vitro characterization of potent peptidic inhibitors of DENV protease with a sulfonyl moiety as N-terminal cap, thereby creating sulfonamide-peptide hybrids. The in-vitro target affinities of some synthesized compounds were in the nanomolar range, with the most promising derivative reaching a K i value of 78 nM against DENV-2 protease. The synthesized compounds did not have relevant off-target activity nor cytotoxicity. The metabolic stability of compounds against rat liver microsomes and pancreatic enzymes was remarkable. In general, the integration of sulfonamide moieties at the N-terminus of peptidic inhibitors proved to be a promising and attractive strategy for further drug development against DENV infections. [Display omitted] • Sulfonamide-peptide hybrids were designed and synthesized. • Dengue virus protease is inhibited in-vitro with high potency. • High target selectivity and metabolic stability. [ABSTRACT FROM AUTHOR]

A series of new 5-substituted 1 H-tetrazoles bearing bioactive N-heterocyclic cores were synthesized through [3 + 2] cycloaddition reactions between alkyl nitriles (RCN) and NaN3 in the presence of Cu/aminoclay/reduced graphene oxide nanohybrid (Cu/AC/r-GO nanohybrid) as a heterogeneous nanocatalyst in water/ i-PrOH (50:50, V/V) media at reflux condition. The influence of factors on a sample reaction including solvent type, temperature, and catalyst amount was discussed. This current protocol has many advantages including inexpensiveness, environmentally benign, broad substrate scope, excellent yields, and easy work-up procedure. The Cu/AC/r-GO used in this protocol is a low-cost catalyst that proved to have considerable chemical and thermal stabilities. This non-hygroscopic catalyst can be easily recycled, reused, and stored for many consecutive reaction runs without significant loss in its reactivity. [ABSTRACT FROM AUTHOR]

A convenient and facile four-component synthesis is described of 2-amino-3-cyanopyridine derivatives from readily available starting materials catalysed by doped nano-sized Cu2O on melamine-formaldehyde resin (nano-Cu2O-MFR). In this method, treatment of different aldehydes, ketones, malononitrile, and ammonium acetate in refluxing H2O/EtOH (1:1) in the presence of doped nano-Cu2O-MFR as a highly efficient heterogeneous catalyst affords the corresponding 2-amino-3-cyanopyridines in good to excellent yields. The nano-Cu2O-MFR is a cheap and stable nano-catalyst that could be easily recovered and reused for many consecutive reaction runs without considerable decrease in its activity. [ABSTRACT FROM AUTHOR]