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An asymmetric Baylis–Hillman reaction protocol has been developed using a chiral pyrrolidine based organocatalyst. The catalytic loading works well with a wide range of aromatic aldehydes to afford the corresponding β-hydroxy acrylate with high enantioselectivity up to 100% with excellent yields. The organocatalyst shows excellent enantioselectivity with 10 mol% of catalytic loading at room temperature condition.

Novel two L-proline analogues as thiourea organocatalysts were synthesised, first is the assembly of a structurally well-defined cyclohexane scaffold with a thiourea moieties and amine functionalities could constitute a new class of organocatalysts. Second is the triazole-3-thione analogue. The first one found to be efficient catalysts for the direct asymmetric aldol reaction between ketone and aromatic aldehydes. The catalysts exhibited high catalytic activity, diastereoselectivity and excellent enantioselectivity at room temperature with a low loading.

A green protocol for an effective synthesis of bioactive polyhydroquinoline derivatives was developed via condensation of substituted salicylaldehyde, dimedone, ethyl acetoacetate and ammonium acetate catalyzed by 3-methyl-1-sulfonic acid imidazolium chloride ([Msim]Cl) in excellent yield. All synthesized derivatives were evaluated for inhibition of cancer cells. The initial assays reveals that some of the synthesized derivatives show significantly satisfactory inhibition activities against human breast cancer cells (MCF7) compared with the control (Adriamycin), which might be developed as novel lead scaffold for potential anticancer agents.

The proline based chiral organocatalyst has been found to be an efficient catalyst for the facile synthesis of substituted 2-aryl-2H-chromenes-3-carbaldehyde. We envisioned that the iminium interaction between chiral amino catalysts and α,β-unsaturated carbonyl group was beneficial along with thiourea group as hydrogen bond donor, heterocyclic amines as general base in the domino oxa-Michael-aldol reaction. This catalytic system provided the products in good to high yields (73%–96%) with excellent enantioselectivity (up to 97%) and reasonable reaction time. The atom economy, high yield and mild reaction conditions are some of the important features of this protocol.

l -Proline has been employed efficiently for the synthesis of chromeno-chromenone derivatives via a one-pot, three component condensation reaction of salicylaldehydes, 4-hydroxy coumarin, and indole or barbituric acid. The simple procedure and good to excellent yields (78–90%) are notable features of the method. The obtained derivatives were studied for their molecular docking as an anti-HIV-1 RT.

In an attempt to design and synthesize a new class of anti-HIV-1 RTIs i.e., 4-(phenyl)-N,N-bis((1-phenyl- 1H-1,2,3-triazol-4-yl)methyl)thiazol-2-amine derivatives, substituted 2-amino-4-phenylthiazoles were alkylated with propargyl bromide to obtain dialkyne 2-amino-4-phenylthiazoles. This dialkyne 2-amino-4-phenylthiazole was reacted with aryl azides to generate small library of 15 compounds (4a-o) by click chemistry. The obtained derivatives were studied for as an anti-HIV-1 NNRT Inhibitors. All synthesized compounds of 1,2,3-triazolylphenylthiazole series were be docked into the non-nucleoside inhibitor binding pocket (NNIBP) of HIV-1 RT and highly inhibiting derivatives studied for in vitro anti-HIV-1 assay.

An efficient asymmetric synthesis of homoallylic alcohols is described by the allylation of carbonyl compounds using organocatalysts as chiral directors in the presence of tin metal. The effect of chiral environment is also studied on the allylation reactions. This method allows us to obtain two different enantiomers of homoallylic alcohol in the presence of the corresponding chiral compound. The protocol is applied to various aldehydes to obtain high yields and excellent enantioselectivities for the corresponding homoallylic alcohols.

Method describes asymmetric reaction of triethyl phosphites and 2-arylidenemalononitrile catalysed by the chiral organocatalyst in solvent ethanol. The organocatalyst effectively catalyse reaction to give β-malonophosphonates in high yields (85–64%) and good to moderate enantiomeric excess (78–53%).

3-Chlorophenylboronic acid promotes efficient synthesis of 3-substituted indole derivatives via aza-Friedel–Crafts reaction of indoles, aromatic aldehydes, and N,N-dimethylaniline at room temperature. The mild reaction conditions, excellent yields, and easy experimental workup are striking features of this procedure for synthesis of 3-substituted indoles.

This present method deals with an exceedingly rare aspect of α-aminophosphonate synthesis. We studied an enantioseletive one-pot synthetic method for the syntheses of optically active α-aminophosphonates by employing an organocatalyst. Some new organocatalysts were synthesized and studied for their reactivity and enantioselectivity. The organocatalyst effectively catalyzed the reaction and provided the corresponding α-aminophosphonates in high yields (71–90 %) with excellent enantiomeric excess values (73–92 %).

Phenylboronic acid has been found to be an efficient catalyst for the synthesis of 1,5-benzodiazepine derivatives via cyclocondensation of o-phenylenediamine and various ketones in good to excellent yields (82–91%) using acetonitrile as solvent at reflux condition. The remarkable advantages offered by this method are easy mild reaction condition, experimental work up and good to excellent yields of products.

A new series of 1H-pyrazole derivatives 5a–j bearing an aryl sulfonate moiety have been synthesized by a one-pot cyclo-condensation reaction of 2-(3-(dimethylamino)acryloyl)phenyl-4-methyl benzene sulfonates 4a–e and hydrazine hydrate or phenyl hydrazine in ethanol under reflux conditions. Some of the newly synthesized compounds were screened for their anti-inflammatory activity. All synthesized compounds were screened against Gram positive and Gram negative bacterial and fungal strains. The compound 5b was found to be a potent anti-inflammatory agent while the majority of the compounds were found to be active against microbial strains.

The molecular iodine-catalyzed direct coupling of indoles with 1,3-dicarbonyl compounds is described. This new method for C–C bond formation allows high functional group tolerance, regioselectivity, and scope under mild conditions.

We have developed an efficient protocol for the synthesis of $$\upbeta $$ -amino carbonyl compounds using phenylboronic acid as effective and eco-friendly catalyst via one-pot three-component Mannich reaction. Excellent yields, mild reaction condition, and simple experimental work-up procedure are some of the advantages of this method, which makes it a useful protocol for the synthesis of $$\upbeta $$ -amino carbonyl compounds.

The three-component reaction between salicylaldehydes (I), 4-hydroxycoumarin (II) and indole (III) or barbituric acid (V) furnishes the corresponding chromeno[4,3-b]chromen-6-ones in high yields.

18 Title compounds of type (IV) or (VI) are prepared and tested as anti-HIV-1 RT inhibitors.

An efficient synthesis of dicycloalkenopyridines was achieved via one-pot three-component condensation of aromatic aldehyde, cyclohexanone, and hydroxylamine hydrochloride using 3-nitrophenylboronic acid as an efficient catalyst under ambient condition. The current methodology offers several advantages such as high yields (78–90%) and simple experimental work-up at ambient temperature conditions.

A simple, inexpensive and efficient one-pot synthesis of piperidine derivatives was achieved in excellent yield via the three-component reaction of substituted aniline, 1,3-dicarbonyl compound and aromatic aldehyde using phenylboronic acid as catalyst.

The solid-supported fluoroboric acid (SiO2-HBF4) was found to be a mild and highly effective catalyst for s-alkylation of thiols with alcohols under solvent free condition.

Scandium triflate efficiently promotes a one-pot, three-component condensation of aldehydes, malononitrile, and thiophenols to produce highly substituted pyridines in good yields. This reaction does not involve any hazardous organic solvent and toxic catalyst.

Using hydrogen bond based concept we have synthesized new organocatalysts and have applied them to catalyze direct asymmetric aldol reaction. Reaction proceeded efficiently and gave high yield with excellent diastereoselectivity and enantioselectivity.

A convenient protocol has been developed for the synthesis of Baylis–Hillman adducts in the presence of a base and an organocatalyst. We have designed and synthesized organocatalysts based on hydrogen bonding using a pyrrolidine ring as the backbone and applied them to Baylis–Hillman transformations. This method provides products in good to high yields (73–90%) and with excellent enantiomeric excesses (up to 96%) and reasonable reaction times.

We report the novel synthesis of azetidin-2-one derivatives containing aryl sulfonate moiety from the reaction of 2-hydroxy benzaldehyde with p-toluene sulfonyl chloride afforded firstly 2-formylphenyl 4-methylbenzene sulfonate (2). The compound (2) on reaction with p-aminobenzoic acid or 2-aminopyridine gave the corresponding aldimines (3). Furthermore, the aldimines are on reaction with chloroacetyl chloride gives corresponding azetidin-2-ones in good to moderate yield. Among the eight synthesized azetidin-2-ones, five selected compounds have been screened for the an-ti-inflammatory activity, few of them showed good anti-inflammatory activity compared with standard drugs. Anti- microbial activity of all synthesized compounds has been tested and most of the compounds showed good anti-bacterial and anti-fungal activities.

An efficient synthesis of substituted 1-pyridylimidazo-[1,5-a]-pyridines has been accomplished using scandium(III) triflate as catalyst under mild conditions in excellent yields.

cis-2-Aminocyclohexylcarbamoylphosphonic acid ( cis-ACCP) was evaluated in vitro and in two in vivo cancer metastasis models. It reduced metastasis formation in mice by approximately 90% when administered by a repetitive once daily dosing regimen of 50 mg/kg via oral or intraperitoneal routes and was nontoxic up to 500 mg/kg, following intraperitoneal administration daily for two weeks. Pharmacokinetic investigation of cis-ACCP in rats revealed distribution restricted into the extracellular fluid, which is the site of action for the antimetastatic activity and rapid elimination ( t 1/2 approximately 19 min) from blood. Sustained and prolonged absorption ( t 1/2 approximately 126 min) occurred via paracellular mechanism along the small and large intestine with overall bioavailability of 0.3%. The in vivo concentrations of cis-ACCP in the blood in rats was above the minimal concentration for antimetastatic/MMP-inhibitory activity, thus explaining the prolonged action following once daily administration. Finally, 84% of the intravenously administered cis-ACCP to rats was excreted intact in the urine.

Low molecular weight compounds were isolated by high-performance liquid chromatography from the maggot or haemolymph extracts of Lucilia sericata (Meigen) (Diptera: Calliphoridae). Using gas chromatography-mass spectrometry analysis, three compounds were obtained: p-hydroxybenzoic acid (molecular weight 138 Da), p-hydroxyphenylacetic acid (molecular weight 152 Da) and octahydro-dipyrrolo[1,2-a;1',2'-d] pyrazine-5,10-dione (molecular weight 194 Da), also known as the cyclic dimer of proline (or proline diketopiperazine or cyclo[Pro,Pro]). All three molecules revealed antibacterial activity when tested against Micrococcus luteus and/or Pseudomonas aeruginosa, and the effect was even more pronounced when these molecules were tested in combination and caused lysis of these bacteria.

A new series of pyrazole, isoxazole, benzoxazepine, benzothiazepine and benzodiazepine derivatives were prepared by the multi-component cyclo-condensation reaction of 1-phenyl-3-(2-(tosyloxy)phenyl)propane-1,3-dione, N,N-dimethylformamide dimethyl acetal and hydrazine or hydroxylamine hydrochloride or 2-aminothiophenol or 2-aminophenol or benzene-1,2-diamine using μwave technique in aqueous media. All the synthesized compounds were evaluated for their anti-bacterial and antifungal activities. Some of the selected compounds were also screened for their anti-inflammatory activity. Keywords: Pyrazole, Isoxazole, Benzothiazepine, Benzoxazepine, Benzodiazepine, Anti-inflammatory

Some new 2,3-diaryl-1,3-thiazolidin-4-one derivatives having a 2,6-dichlorophenyl, antipyrine, or 1,2,4-triazole ring at N-3 and variously substituted 3-iodo- or 3-bromo-phenyl rings at C-2 have been synthesized and tested as antibacterial agents. The results of the in vitro tests showed that some of them have effective antibacterial activity.

The use of molecular iodine as the catalyst for a one-pot synthesis of quinoxaline derivatives at room temperature is reported.

An efficient protocol was developed for the synthesis of 3-aminoalkylated indoles using 3-chlorophenylboronic acid as a catalyst under ambient temperature conditions. The three-component reaction of indoles, aromatic aldehydes and N -methyl aniline offered corresponding 3-aminoalkylated indoles in excellent yields. This protocol presents some remarkable features such as mild reaction conditions, simple workup procedure and excellent yields.

Some new 3,5-diphenyl and 1,3,5-triphenyl-2-pyrazolines derivatives were synthesized by reacting 1,3-diphenyl-2-propen-1-ones with hydrazine hydrates and phenyl hydrazine in ethanol. The structural elucidation of the compounds was performed by IR, 1 H NMR and elemental analysis. All examined compounds showed appreciable antibacterial activity.

A novel method for the synthesis of 2 or 3-substituted 5,6-dihydro-6,11-dioxo-morphanthridines (2) involving the cyclisation of anilinic acid (1) with PPA/AcOH has been developed. A new heterocyclic system, 2 or 3-Substituted 5,6,11,12-tetrahydrodibenzo[b, f] [1,4]diazocine-6,11-diones (4) has been synthesized with excellent yields.

Both enantiomers of the title compounds can be obtained by a simple change in the ligand structure under otherwise identical conditions.

Phospha—Michael addition of P(O—Et)3 to benzylidenemalononitriles (I) in the presence of a proline-based organocatalyst represents one of the most straightforward routes for the synthesis of optically active β-malonophosphonates (III) (13 examples).

This present method deals with an exceedingly rare aspect of α-aminophosphonate synthesis. We studied an enantioseletive one-pot synthetic method for the syntheses of optically active α-aminophosphonates by employing an organocatalyst. Some new organocatalysts were synthesized and studied for their reactivity and enantioselectivity. The organocatalyst effectively catalyzed the reaction and provided the corresponding α-aminophosphonates in high yields (71–90 %) with excellent enantiomeric excess values (73–92 %).

A variety of ortho-hydroxy substituted aromatic carbonyl compounds were regioselectively iodinated with iodine and iodic acid in excellent yields.

Thiols are oxidized to the corresponding disulfides with a mild base, anhydrous potassium phosphate, under ambient conditions in the presence of air.

A novel and eco-friendly method for the asymmetric Henry reaction of aldehydes is developed.

An efficient protocol was developed for the synthesis of 3-aminoalkylated indoles using 3-chlorophenylboronic acid as a catalyst under ambient temperature conditions. The three-component reaction of indoles, aromatic aldehydes and N -methyl aniline offered corresponding 3-aminoalkylated indoles in excellent yields. This protocol presents some remarkable features such as mild reaction conditions, simple workup procedure and excellent yields.

A series of new organocatalysts is designed based on hydrogen bonding motifs and applied to the title reaction.

An efficient synthesis of dicycloalkenopyridines was achieved via one-pot three-component condensation of aromatic aldehyde, cyclohexanone, and hydroxylamine hydrochloride using 3-nitrophenylboronic acid as an efficient catalyst under ambient condition. The current methodology offers several advantages such as high yields (78–90%) and simple experimental work-up at ambient temperature conditions.

PTF is found to be the catalyst of choice for the direct asymmetric aldol reaction of cyclohexanone with aromatic aldehydes to yield the adducts with (nearly) complete diastereoselectivity and good enantioselectivity under optimized conditions.