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In nearly all cases of biological activity of sulfated GAGs, the sulfate group(s) are critical for interacting with target proteins. A growing paradigm is that appropriate small, sulfated, nonsaccharide GAG mimetics can be designed to either mimic or interfere with the biological functions of natural GAG sequences resulting in the discovery of either antagonist or agonist agents. A number of times these sulfated NSGMs can be computationally designed based on the parent GAG-protein interaction. The small sulfated NSGMs may possess considerable aromatic character so as to engineer hydrophobic, hydrogen-bonding, Coulombic or cation-pi forces in their interactions with target protein(s) resulting in higher specificity of action relative to parent GAGs. The sulfated NSGMs can be easily synthesized in one step from appropriate natural polyphenols through chemical sulfation under microwave-based conditions. We describe step-by-step procedures to perform microwave-based sulfation of several small polyphenol scaffolds so as to prepare homogenous NSGMs containing one to more than 10 sulfate groups per molecule in high yields.

Metal-organic frameworks (MOFs) have commanded significant attention in recent years on account of the applicability of these materials across several disciplines in material chemistry. The liberty of tuning the coordination nanospaces owing to the infinite choice of organic linkers and multivariate oxidation states of the metal nodes bestows a distinguished advantage of designable architectures to this class of materials. Majority of the reported MOFs comprise of neutral frameworks as the net positive charge on the metal ions is satisfied by the negative charge of anionic ligands or the coordinated anions of the metal salt used in synthesis. Although being non-trivial, the synthesis of ionic MOFs (iMOFs) affords several distinct advantages over the routine neutral frameworks by virtue of the isolated charged species in confined nanospaces. The development and potential applications of such cationic or anionic frameworks has been discussed thoroughly in this review. The design principles governing the formation of such charge-polarized MOFs have been outlined through representative examples. The state-of-the-art ion exchange performances of competing materials have been compared and a future perspective of such ionic-MOFs is proposed.

This short review gives a focussed discussion on metal–organic frameworks (MOFs) made of neutral N-donor ligands which show structural flexibility under various exogenous stimuli. Chemical stimuli such as presence of anions, free guests, coordinated guests and physical stimuli (light, heat and so on) render structural flexibility in MOFs. Single-crystal-to-single-crystal transformation studies have attracted a lot of attention for the understanding of such flexible MOF materials. Such a dynamic structural behavior with proper host–guest interactions gives very interesting functions such as chemical separation, sensing and magnetic properties and so on.

Magnetically separable cobalt ferrite nanoparticles (CoFe2O4, NPS) have been demonstrated for the first time as an efficient catalyst in Petasis-Borono–Mannich (PBM) reaction between salicylaldehydes, sec. amines and aryl boronic acids to furnish alkylaminophenols in high yields. Relatively shorter reaction times, easy purification of the products and reusability of the catalyst for five consecutive runs without appreciable loss in it's activity are the noteworthy features of the developed protocol.

A simple and efficient process for an exclusive mono-Michael addition of active methylene compounds to conjugated esters, nitriles and ketones is developed. An ionic liquid-mediated reaction is carried out at room temperature. A reaction carried out at 60 °C resulted in a double-addition product. A mechanism is proposed and supported by P31 and DOSY NMR analysis of the used ionic liquid.

The entitled organocatalyst is non-toxic, cheap, bio-degradable and easy to handle, and is used in the synthesis of pyran-annulated heterocycles for the first time.

An efficient synthesis of pyrrole diesters from readily available aromatic, benzylic, and aliphatic nitriles with ethyl bromoacetate takes place if the amount of the catalyst is 50 mol%.

Alkynyl aziridines can be obtained from the catalytic asymmetric aziridination (AZ reaction) of alkynyl imines with diazo compounds in high yields and high asymmetric inductions mediated by a chiral boroxinate or BOROX catalyst. In contrast to the AZ reaction with aryl- and alkyl-substituted imines, alkynyl imines react to give cis-substituted aziridines with both diazo esters and diazo acetamides. Remarkably, however, the two diazo compounds give different enantiomers of the cis-aziridine from the same enantiomer of the catalyst. Theoretical considerations of the possible transition states for the enantiogenic step reveal that the switch in enantiomers results from a switch from Si-face to Re-face addition to the imine, which in turn is related to a switch from reaction with an E-imine in the former and a Z-isomer of the imine in the latter.

via oxidative cyclization of α,β-unsaturated ketoximes (I) or (III), resp., using IBX as efficient, environmentally friendly and nontoxic oxidation reagent

A new series of quinolinylpyrazolinylthiazole derivatives (V) (12 examples) is synthesized from chalcones (I).

A variety of new chromenylpyridinyl sulfonamides (VI) (13 examples) are synthesized and screened for their antibacterial and antifungal activities.

A series of 2,5-dihydro-4-[1'-(o-chlorophcnyl)-3'-methyl-5'-pyrazolidene azomethine]-2-(substituted phenyl)-1,5 benzothiazepines 7a-j have been synthesized using environmentally benign procedure and evaluated for their antimicrobial activity. Neat reactants on microwave irradiation (MWI) under solvent-free-condition resulted in enhancement of yields and reaction rates. Structures of the synthesized compounds have been elucidated on the basis of their elemental analyses and spectral data.

Several 2-aryl-3-[4-(4-chlorophenyl)-6-(3,4,5-trimethoxyphenyl)pyrimidin-2-yl-ureido]-4-thiazolidinones 5a-j and 1-[4-(4-chlorophenyl)-6-(3,4,5-trimethoxyphenyl)pyrimidin-2-yl-ureido]-3-chloro-4-aryl-2-azetidinones 6a-j have been synthesized and tested for their antibacterial, antifungal and antitubereulosis activities against different microorganisms. Tlic structure ol' novel synthesized compounds have been established on the basis of elemental analyses, 1 H NMR and IR spectral data.

An efficient and extremely fast procedure for the synthesis of 4-aryl-3-chloro-1-[(2-benzothiazolylthio)acetamidyl]-2azetidinone 4 by the reaction of arylidene-[(2-benzothiazolylthio)acetamidyl] 3 with chloroacetylchloride in DMF in the presence of catalytic amount of triethylamine under microwave irradiation is described. A considerable increase in the reaction rate has been observed with better yield. All the compounds have been screened for their antifungal activity against Candida albicans and Aspergillus niger, and antibacterial activity against Escherchia coli, Staphylococcus aureus and Bacills substilis. In the primary screening, some of the compounds exhibit appreciable activity. The structures of the synthesised compounds 4a-j have been characterized on the basis of their elemental analysis and spectral data.

Condensation of p-nitrobenzoylhydrazide 1 with substituted aromatic aldehydes 2 under microwave irradiation and by conventional method provide Sehiff bases 3a-j. Schiff bases 3a-j on condensation with diazonium salt of 6-mcthoxy-2-aminobenzothiazole give formazans 4a-j. This reaction is carried out only by conventional method.

2-[4-(4-Chlorophenyl)-6-(3,4,5-trimethoxyphenyl)pyrimidin-2-ylamino]-4,6-dichloro-s-triazine (2), derived from 2-amino-4-(4-chlorophenyl)-6-(3,4,5-trimethoxyphenyl)pyrimidine (1) and 2,4,6-trichloro-1,3,5-s-triazine, on treatment with morpholine gave 2-[4-(4-chlorophenyl)-6-(3,4,5-trimethoxyphenyl)pyrimidin-2-ylamino]-4-(morpholino)-6-chloro-s-triazine (3). Compound 3 when reacted with different arylthioureas in the presence of weak base gave new 2-[4-(4-chlorophenyl)-6-(3,4,5-trimethoxyphenyl)pyrimidin-2-ylamino]-4-(morpholino)-6-(arylthioureido)-s-triazines (4a-j). The compounds were screened for their antibacterial, antifungal and antitubercular activities.

A modified Feist—Benary furan synthesis is developed that involves a lithium aldol reaction between a methyl ketone and an α-chloroaldehyde followed by a thermally induced tetrahydrofuran formation/dehydration sequence and affords 2,5-disubstituted furans in decent overall yield.

Some of the title compounds (V), e.g. (Vc)—(Vf), show potent antibacterial activity against bacterial strains at no-cytotoxic concentrations.

The novel protocol uses KBrO3 as the oxidant and Pd-C as the catalyst and provides an environmentally benign alternative to the traditional Wacker system.

Efforts to address HIV infection have been highly successful, enabling chronic suppression of viral replication with once-daily regimens. More recent research into HCV therapeutics have also resulted in very promising clinical candidates. This Digest explores similarities and differences in the two fields and compares the chronology of drug discovery relative to the availability of enabling tools, and concludes that safe and convenient, once-daily regimens are likely to reach approval much more rapidly for HCV than was the case for HIV.

A variety of new fluorobenzamide derivatives (X) (15 examples) are synthesized using conventional or microwave chemistry and evaluated for their antimicrobial activities.

Two novel series of quinoline derivatives substituted with thiazolylpyrazole (V) or pyrimidine moieties (XI) are synthesized (yields not given) and screened for their antimicrobial activities.

The synthesized compounds (V) show potent inhibitory action against Gram-positive and Gram-negative bacteria and against different strains of fungi.

Compounds (III), combining biologically relevant quinoline, oxadiazole and azetidinone structural units in one molecule, show moderate to excellent antibacterial and antifungal activities.

Some of the heterocycles exhibit marked antibacterial and/or antifungal effects: compounds (Va), (Vf) and (XIa) reveal an excellent activity against E.

An efficient and fast synthesis of the title compounds (III) (11 examples) is achieved by reaction of salicylaldehyde (I) with Meldrum′s acid using potassium phosphate as an inexpensive catalyst.

Three series of novel quinolylpyrazole derivatives (IV), (VI) and (VIII) are synthesized by condensation reactions of propenone derivatives (III) with hydrazine or semicarbazide derivatives under conventional heating or microwave irradiation conditions.

Advantages of the title reaction are the ambient conditions, the short time and the easy work-up procedure.

Heck reactions are used for the synthesis of a variety of anthracene-9-monoacrylamide and bisacrylamide derivatives.

A wide variety of carbonyl compounds can be transformed to their corresponding cyanohydrins in a single step and without any catalyst using DMSO/water as reaction medium.

New pyrimidine derivatives (III) and pyrazoline derivatives (IV) and (VI) possess only low antibacterial activities compared to reference drug streptomycin.

12 Title compounds of type (VII) are prepared and their antibacterial and antifungal activities are investigated.

Almost all the new compounds (III), (V) and (VI) show mild to moderate antibacterial and antifungal activities.

A convenient and cost-effective synthesis of pharmacologically important tert-butyl-2-(4-2-aminoethyl)phenylthio)-2-methylpropanoate from commercially available 2-2-phenyl-1-ethanol is described.