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The aldol reaction which is the most important one among the C-C bond forming reactions, is widely used by synthetic organic chemists to obtain β-hydroxycarbonyl compounds which are important starting components for biologically active compounds in optically pure form. In this research, five Pro-Phe derivatives were synthesized by simple amidation reactions and characterized by their spectral data. Their catalytic activities in asymmetric aldol reaction were investigated. The catalytic activity studies were performed with aliphatic ketones and various aromatic aldehydes. Especially, (S)- methyl 3-mercapto-2-((S)-3-phenyl-2-((S)-pyrrolidine-2-carboxamido)propanamido)propanoate showed good catalytic activities in water at 0oC in the presence of p-nitrobenzoic acid cocatalyst. The enantioselectivities were up to 90.4%, the diastereomeric ratios were up to 97/3 and yields were 99%. The results showed that these organocatalysts were promising organocatalysts for aldol reaction. Besides, this catalyst showed its best catalytic activities in water which is also an important contribution to green chemistry requirements.

New di- or triamide organocatalysts derived from (L)-proline were synthesized and successfully used in the direct asymmetric aldol reaction of aliphatic ketones and aromatic aldehydes in water at 0 °C in the presence of benzoic acid as co-catalyst. (S)-methyl-2-((S)-3-hydroxy-2-((S)-3-pyrrolidine-2-carboxamido)propanamido)-3-phenylpropanoate (7c) as organocatalyst showed best results under these reaction conditions, and good diastereoselectivities (up to 99%), enantioselectivities (up to 98%) and yields (up to 91%) were observed.

Sulfuric acid immobilized on silica gel is used as an efficient catalyst in the synthesis of N-substituted pyrrole derivatives by the Clauson–Kaas pyrrole synthesis. The solvent free reaction mixture is stirred by grinding. Within very short reaction time the process leads to the corresponding products without any decomposition recorded.

Several high solid content waterborne polyurethane dispersions (WPUDs) with the combination of anionic and nonionic stabilization were synthesized by polyaddition reaction using isophorone diisocyanate (IPDI), trimethylol propane (TMP) and 1,6-hexanediol (HDO) as the hard segments, polypropylene glycol with molecular weight of 2000 Da (PPG-2000), and polytetramethylene ether glycol with molecular weight of 2000 Da (PTMG-2000) as the soft segments, anionic diol dimethylol propionic acid (DMPA) and nonionic diol Y-mer N 120 (NID) as the donors of hydrophilic groups. The chain extension reaction between residual NCO groups was made by using hydrazine (HYD). The effects of the combination of anionic and nonionic monomer and macrodiol types on the performance of the WPUDs were studied in terms of particle size distribution and dispersion stability. The results showed that the WPUDs exhibited narrow particle size distribution, good appearance and good mechanical properties.

The aim of this study was to develop a novel nanosize drug candidate for cancer therapy. For this purpose, (S)-methyl 2-[(7-hydroxy-2-oxo-4-phenyl-2H-chromen-8-yl)methyleneamino]-3-(1H-indol-3-yl)propanoate (ND3) was synthesized by the condensation reaction of 8-formyl-7-hydroxy-4-phenylcoumarin with l-tryptophan methyl ester. Its controlled release formulation was prepared and characterized by different spectroscopic and imaging methods. The cytotoxic effects of ND3 and its controlled release formulation were evaluated against MCF-7 and A549 cancer cell lines, and it was found that both of them have a toxic effect on cancer cells. For drug design and process development, the molecular docking analysis technique helps to clarify the effects of some DNA-targeted anticancer drugs to determine the interaction mechanisms of these drugs on DNA in a shorter time and at a lower cost. By using the molecular docking analysis and DNA binding assays, the interaction between the synthesized compound and DNA was elucidated and non-binding interactions were also determined. To predict the pharmacokinetics, and thereby accelerate drug discovery, the absorption, distribution, metabolism, excretion and toxicity values of the synthesized compound were determined by in silico methods.

In this study, the aim was computer-aided design of a new anti-cancer drug molecule. For this purpose, 7-hydroxy-8-(((1-hydroxy-3-phenylpropan-2-yl)imino)methyl)-4-(trifluoromethyl)-2H-chromen-2-one (D3) was synthesized by the condensation reaction. Its characterization studies were performed by NMR, FTIR, MS and UV spectral data. Anti-cancer activity of D3 was examined on MCF-7, HeLa and Mat-Lylu cell lines, and it was found that D3 showed cytotoxic activity in all cell lines. Mutagenity of D3 was determined by Ames/Salmonella assay, and it was found that it had no mutagenic effect on S. typhimurium TA98 and TA100 strains. Antioxidant activity of D3 was also revealed. Besides, the interaction of D3 with DNA was investigated by the UV titration method. Experimental results showed D3 binds to DNA by intercalation or groove linking. Moreover, molecular docking approach was used to elucidate the atomic level interaction between the synthesized compound and DNA; thus, the atomic level behavior of the compound in the binding site of DNA was characterized and its binding properties were determined. In addition, the physicochemical and pharmacokinetic properties of the synthesized compound were performed using ADMET and frontier orbital analyses. In conclusion, according to both in vitro and in silico findings, it can be suggested that D3 may be used as a new anti-cancer drug for breast, cervical and prostate cancers.

Herein, a novel coumarin-based fluorescent probe (FS3) was designed, synthesized, and characterized. It exhibited significant fluorescence quenching in the presence of Zn2+ ions. Just a minor alteration occurred in the fluorescence intensity of FS3 in the presence of other metals studied. The limit of detection for the determination of Zn2+ by FS3 was calculated to be 3.43 × 10−9 M. Since the Job’s graph of 1/(F0–F) and 1/[Zn2+] had a linear fit, it was determined that the binding stoichiometry between the FS3 and Zn2+ was 1:1. The association constant of the system was found to be 2.39 × 104 M−1 and confirmed by ESI-MS and FT-IR. It was demonstrated that the developed highly reversible sensor system works by performing real sample analysis. Moreover, the FS3 which has shown no toxicity and displayed a strong fluorescence image will act as an efficient and non-destructive sensor for the determination of Zn2+ in living organisms.

Catalytic activities of (3S)-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (THIQA)-based mono- and dipeptides and their l -proline analogs in asymmetric aldol reaction were investigated. THIQA-based dipeptides showed better enantioselectivity than proline analogs, whereas proline-based dipeptides gave higher yield in the aldol reaction of cyclohexanone with several aldehydes in dichloromethane at −10 °C in the presence of benzoic acid.

Long chain dicationic ammonium salts were used successfully as phase transfer catalyst in the condensation reactions of aromatic aldehydes in water under ultrasonic irradiation for the first time. The quaternary salt having longer distance between the cation centers was more effective than the mono- and dicationic ones having short chain.

N-Substituted homochiral pyrrole derivatives were synthesized by the ring-closure reaction of cis-1,4-dichloro-2-butene with various amine compounds on a silica surface under microwave irradiation.

Homochiral 2-methylpyrrole derivatives are synthesized in high yields starting from chiral amines, amino alcohols and amino acid esters. The photooxygenation of these pyrrole derivatives in the presence of a photosensitiser furnishes the corresponding α,β,γ,δ-unsaturated γ-lactams as the major products in good yields.

Catalytic activities of (3S)-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (THIQA)-based mono- and dipeptides and their l -proline analogs in asymmetric aldol reaction were investigated. THIQA-based dipeptides showed better enantioselectivity than proline analogs, whereas proline-based dipeptides gave higher yield in the aldol reaction of cyclohexanone with several aldehydes in dichloromethane at −10 °C in the presence of benzoic acid.

A chemoenzymatic synthesis of pharmacological interesting ( R )-2-hydroxypropiophenones starting from propiophenone derivatives is described. Manganese(III) acetate-mediated acetoxylation followed by fungus-mediated hydrolysis of propiophenone derivatives affords ( R )-2-hydroxypropiophenones in high enantiomeric excess.

The catalytic potential of imidazolium salts in the benzoin condensation was investigated. Various aromatic aldehydes were tested in the benzoin condensation under the optimised protocol to afford α-hydroxyketones using N-heterocyclic carbenes derived from mono- and dicationic imidazolium salts. The products were obtained in good yields within short reaction times. Dicationic imidazolium salts with a long aliphatic chain between the imidazole rings were found to be more effective pre-catalysts for the benzoin condensation in comparison to the corresponding monocationic salts having the same aliphatic chain length.

A new procedure to synthesize the N-substituted pyrrole derivatives by Clauson Kaas reaction catalyzed by acidic ionic liquid under microwave irradiation was developed. This procedure provides several advantages such as high yield, clean product formation, and short reaction time.

The molecule of the title compound, C18H15ClN2, is not planar. The dihedral angle between the quinoline and phenyl rings is 116.2 (1)degrees. Bond lengths and angles are normal.

Long chain dicationic ammonium salts are successfully used as phase-transfer catalysts in the condensation reactions of aromatic aldehydes in water under ultrasonic irradiation.

Among the imidazolium compounds (I) and (II), derivative (Ia) is demonstrated to be the most efficient pre-catalyst.

A chemoenzymatic synthesis of pharmacological interesting ( R )-2-hydroxypropiophenones starting from propiophenone derivatives is described. Manganese(III) acetate-mediated acetoxylation followed by fungus-mediated hydrolysis of propiophenone derivatives affords ( R )-2-hydroxypropiophenones in high enantiomeric excess.

Homochiral 2-methylpyrrole derivatives are synthesized in high yields starting from chiral amines, amino alcohols and amino acid esters. The photooxygenation of these pyrrole derivatives in the presence of a photosensitiser furnishes the corresponding α,β,γ,δ-unsaturated γ-lactams as the major products in good yields.

Titration of weak bases in non-aqueous solvents can provide valu- able information about these weak bases. Some primary amines; 1-aminobutane, 1-aminopropane, 2-aminoheptane, aminocyclohexane, 3-amino-1-phenylbutane were titrated with hydrochloric acid in toluene solvent. All the primary amines gave very well-shaped potentiometric titration curves. The same titrations were done with hydrochloric acid in methanol solvent to show the effect of amphiprotic solvent in the titrations with hydrochloric acid. As a result, toluene is a suitable solvent for titrating some of the primary amines potentiometrically with hydrochloric acid.

Treatment of 6,7-dimethyl-2,3-diphenylquinoxaline with sodium in tetrahydrofuran formed a monomeric dianion. The chemical behavior of this dianion was investigated by a variety of reagents. As the result, alkylation reactions gave 1,2-dihydro derivatives, while acylation reactions occured at 1,4-positions. Annulation of the pyrazine ring system was accomplished by treating the dianion with oligomethylene dichlorides, Cl(CH2) n Cl, n = 2–4.

N-Substituted homochiral pyrrole derivatives were synthesized by the ring-closure reaction of cis-1,4-dichloro-2-butene with various amine compounds on a silica surface under microwave irradiation.

The synthesis of new 2,3,5,6-aryl substituted tetrahydro-2H-pyrazolo[3,4-d]- thiazoles 4a-j as potential biologically active compounds by the cyclocondensation of phenyl hydrazine with new 5-arylidene derivatives 2a-j of 2,3-disubstituted-1,3- thiazolidin-4-ones 1a-e is reported.

Efficient synthesis of 1,2-disubstituted homochiral pyrroles has been achieved by a two-component coupling of chloroenones and amine compounds on the surface of silica gel without any solvent under microwave irradiation.

Homochiral 2-methylpyrrole derivatives are synthesized in high yields starting from chiral amino alcohols and 5-chloro-3-pentene-2-one. The photooxygenation of these compounds in the presence of a photosynthesizer furnishes the pyrrolooxazolone structures in high diastereoselectivities. In all of the examples, trans-isomers are formed as the major products.

Oxadiazole derivatives which belong to an important group of heterocyclic compounds have been subject of extensive study in the recent past. Numerous reports have appeared which highlight their chemistry and. use1–3. Diverse biological activities such as antituberculostatic, antiinflamatory, analgesic, antipyretic, anticonvulsant, etc. have been found to be associated with oxadiazole derivatives4’5. Because of this reason we aimed to synthesize various 1,3,4-oxadiazole-2-thione derivatives to make remarkable contributions to this class of heterocyclic compounds. Here, we report the synthesis and characterization of some 5-alkyl substituted 1,3,4oxadiazole-2-thiones (3a-e) and 5-alkyl substituted 3-(2,4-dimethylphenyl)1,3,4-oxadiazole-2-thiones (4a-d) by using the synthetic procedure based on the ring closure reactions of appropriate acid hydrazides with carbon disulphide6. We also have synthesized some bis-Mannich bases by the reaction of 3a-e with benzaldehyde and benzidine.

The molecule of the title compound, C19H18N2, is not planar. The dihedral angle between the quinoline and phenyl rings is 118.5 (1)degrees.