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A heterocyclic ligand, 5-(2-(4-chlorophenyl)-1H-benzo[d]imidazol-1-yl)quinolin-8-ol and its Co(II), Ni(II), Cu(II) and Zn(II) complexes were synthesized and characterized by elemental analysis and spectroscopic techniques. According to the spectral analysis, the ligand acts as a bidentate ligand and coordinating through the nitrogen and deprotonated oxygen atoms. For Cu(II) and Ni(II) complexes, spectral analysis reveals square planer geometry, whereas Co(II) and Zn(II) complexes have tetrahedral geometry. The antibacterial results show that Zn(II) complex is more effective than the other metal(II) complexes examined. The ligand and its metal complexes were tested for anticancer activity using the MTT assay with cisplatin as the reference drug against A549, MCF7, and HCT116 cancer cell lines. Results showed that the metal(II) complexes were shown to be more active than the ligand, especially Zn(II) complex being the most potent among this series.

Background: Novel carboxamides and thioureas of 2,3-dihydro-5,6-dimethoxy-2-((piperidin- 4-yl)methyl) inden-1-one were synthesized and their potential anticholinesterase activities were evaluated. The inhibition potency of the compounds 17a-j and 19a-j against AChE was measured and evaluated using Ellman’s spectrophotometric method. Among carboxamides series, compound 17f, 17i, 17j and among thiourea series, compound 19a, 19b were found to be the most active. Methods: The scaffold 2,3-dihydro-5,6-dimethoxy-2-((piperidin-4-yl)methyl) inden-1-one 16, key intermediate of drug donepezil has been synthesised in three steps and derivatised as carboxamides and thioureas for SAR studies. Compounds 17a-j and 19a-j were characterised by 1H NMR and LCMS. The inhibitory activity and antiamnesic effect were studied using different sources such as electric eel AChE, human serum AChE and rat brain homogenate AChE. Results: The results of bioassays indicated that among all the synthesized compounds tested, five compounds 17f, 17i, 17j, 19a and 19b shows IC50 at a dose of 67, 42, 64, 52 and 63 nM respectively against electric eel, human serum and rat brain homogenate, which lead to the suggestion that compound 17i might be considered to be a potent AChE inhibitor. Conclusion: Derivatives of 2,3-dihydro-5,6-dimethoxy-2-((piperidin-4-yl)methyl)inden-1-one with different substitutions were synthesised and tested for their AChE activity. The order of potency is 17i>17j>17f and 19a>19b. The other compounds screened failed to elicit any inhibition of acetyl cholinesterase from rat brain homogenate. It may be concluded from this study that, for effective binding and blocking the AChE activity, molecule needs to bind with peripheral site and active site of the enzyme. Therefore, it can be summarized that by changing the functional group and substitution in the scaffold 2,3-dihydro-5,6-dimethoxy-2-((piperidin-4-yl)methyl)inden-1-one needs to be studied for better AChE inhibitory activity in future research.

The title compound, (4-(6-fluorobenzo[d]isoxazol-3-yl) piperidin-1-yl)(morpholino)methanone was prepared from 3-(piperidin-4-yl)benzo[d]isoxazole and evaluated for antiproliferative activity and structure was characterized using IR, 1H NMR, LC-MS spectra and finally the structure was confirmed by X-ray diffraction studies. The compound crystallizes in the monoclinic crystal system with the space group P21/c. The piperidine ring and the morpholine ring in the title compound adopt a chair conformation with the benzisoxazole ring in the planar conformation within the experimental limits. The molecular structure is stabilized by both inter and intra-molecular hydrogen bonds of the type C—H…O and C—H…N respectively which can account for the stability of the molecule. Further, Hirshfeld surface analysis employing 3D molecular surface contours and 2D fingerprint plots have been used to analyze intermolecular interactions present in the solid state of the crystal.

New thiazole derivatives (2a-l) were synthesized via the reaction of 2-(3-cyano-4-isobutoxyphenyl)-4-methylthiazole-5-carboxylic acid with substituted phenyl amines. The anticancer activity of the synthesized thiazole derivatives was examined against MCF-7 (human breast), MDA-MB-231 (mammary carcinomas), HeLa (Cervical cancer), HT-29, HCT 116 (Colon cancer), and normal chang liver cancer cell lines, whereas cisplatin was employed as a positive control. The anticancer mechanisms were studied via apoptosis assessments, as well as molecular docking. The molecular docking study of potent compounds was carried out against the human epidermal growth factor receptor (HER2, PDB ID: 3RCD) as a possible target for anticancer activity using Auto Dock vina. ADMET results indicated that tested compounds have significant results within the close agreement of Lipinski’s rule of five. In addition, computational work employing density functional theory (DFT) was also carried out at the B3LYP/6-31G (d,p) level to investigate the electronic properties of the potent compounds. The frontier molecular orbital energy and atomic net charges were discussed.

A novel 5-(2-phenyl-1H-benzo[d]imidazol-1-yl)quinolin-8-ol ligand (PBIQ) ligand was used to synthesize a series of Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) complexes. Elemental analysis, FTIR, 1H NMR, UV-Visible and mass spectra were utilized to characterize the newly synthesized ligand and its transition metal complexes. The antimicrobial activity of the ligand and complexes were evaluated against four bacterial and one fungal strain using the minimum inhibitory concentration method (MIC). The minimum inhibition concentration observed was compared against the standard antibiotic rifampicin and the antifungal drug fluconazole. The studies revealed that Cu(II) and Zn(II) complexes are more effective against tested bacterial and fungal strains compared to the ligand and other complexes. Molecular docking techniques revealed that the Cu(II)-PBIQ complex associated with the target protein (PDB ID: 4HL2 ) had a greater binding affinity with π-σ, π-alkyl and hydrophobic interactions. Density function theory (DFT) calculations were applied to evaluate the optimized geometrical structures and to calculate the global reactivity descriptors of the more active Cu(II) and Zn(II) complexes. Besides, the in-silico pharmacokinetics showed that all the examined metal complexes compounds obeyed Lipinski's Rule of five with one violation.

Fluoride is an acute toxin, with a rating slightly higher than lead and is present in ground water naturally or artificially. Groundwater in India displays the presence of harmful quantities of fluoride. Fluorspar is main constituent of sand. Under the ground in presence of water when this mineral gets appropriate condition for dissolution, it gets dissolve in water and fluoride ion’s get separated from sand. The presence of fluoride causes many health issues to human beings. To reduce these health problems, there is a need to remove fluoride ions from water. This article is brief on different techniques for the removal of fluoride from water.

An organo-inorganic photocatalytic nanocomposite material based on conjugated polymer, polyaniline (PANI) with titanium dioxide (TiO2) nanoparticles has been developed by performing in situ chemical oxidative polymerization of aniline with ammonium persulfate (APS) oxidant in the presence of hydrothermally synthesized TiO2 nanoparticles. The structural and morphological properties of TiO2/PANI nanocomposites were analyzed by transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR), respectively. The TEM results of the TiO2/PANI nanocomposites showed that TiO2 nanoparticles of 5–10 nm of sizes are dispersed in the PANI matrix. FT-IR spectra show that the TiO2/PANI nanocomposites are almost identical to the structure of PANI alone. The photocatalytic activities of the nanocomposites were evaluated by the photocatalytic degradation of Rhodamine B (RhB), Methylene Blue (MB) and phenol in the presence of UV-light irradiation. The composite catalysts exhibited higher photocatalytic activity for the degradation of organic pollutants than unmodified TiO2 nanoparticles, which is due to sensitizing effect of PANI.

Adsorption studies of toxic metal ions Cd(II) and Pb(II) onto SnO 2 nanoparticles are presented in this paper. SnO 2 nanoparticles have been prepared via precipitation method and tested for heavy metal ions adsorption. Adsorbent is characterized by XRD, SEM, TEM and BET. SnO 2 nanoparticles are proved to be effective adsorbents for the removal of Cd(II) and Pb(II) ions from solution. They exhibit good adsorption capacity and the adsorption data follow the Langmuir model. The maximum adsorption capacities of 1275.5 and 1265.8 mgg −1 are obtained for Cd(II) and Pb(II), respectively. Adsorption of both the metal ions is found to increase with the increase in temperature indicating exothermic nature of the adsorption process.

Conducting polyaniline (PANI)/vanadium pentoxide (V2O5) nanocomposites have been synthesized by interfacial polymerization technique. The composites have been characterized by X-ray diffraction (XRD), Fourier transforms infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). The electrical conductivity (σac) and dielectric measurements have been carried out in the frequency range of 50 Hz to 1 MHz at ordinary lab temperature. The dielectric constant of the composites has been increased to a very high-value of 3.75 × 105 at lower frequency (1 kHz) for 15 wt% concentration of V2O5 in PANI. The electromagnetic shielding behavior of the composites has been investigated in the frequency range 12–18 GHz (Ku-band) of the microwave region. The shielding results demonstrate the synergistic effect of the composite phases with average shielding effectiveness (SE) values in the range of ~17 to 19 dB (

The title compound [1-(3,5-Dimethyl-2,3-dihydro-isoxazole-4-sulfonyl)-piperidin-4-yl)-diphenyl-methanol was synthesized and the product obtained was characterized by spectroscopic techniques and finally the structure was confirmed by X-ray diffraction studies. The compound crystallizes in the monoclinic crystal system with the space group P21/c and with unit cell parameters a = 8.5280(6) A, b = 25.223(4) A, c = 10.7060(17) A, β = 99.879(8)°, and Z = 4. The structure reveals that the piperidine ring is in chair conformation. The geometry around the S atom is distorted tetrahedral. The structure exhibits both inter- and intramolecular hydrogen bonds of the type O—H···N and C—H···O.

The title compound 1′-Benzyl-8-(4-fluorobenzyl)-8-azaspiro[bicyclo[3.2.1] octane-3,4′-imidazolidine]-2′,5′-dione, C23H23FN3O2 is synthesized and the structure is investigated by X-ray diffraction studies. The compound crystallizes in the triclinic crystal class in the P1 space group. The hydantoin ring adopts a planar conformation and is affected by the π conjugation. The pyrrolidine and piperidine rings in the bicyclo octane moiety adopt envelope and chair conformations respectively. The structure exhibits both inter- and intramolecular hydrogen bonds of the type N-H...O, C-H...O, and C-H...N. The oxygen atom in the hydantoin ring simultaneously accepts two hydrogen bonds to form a three-centered hydrogen bonding pattern.

A series of novel 1-benzhydryl-4-(3-(piperidin-4-yl)propyl)piperidine sulphonamide derivatives 8(a-j) was synthesized in good yield and met the structural requirements essential for anticonvulsant properties. The structures of the synthesized compounds were confirmed on the basis of their spectral data and elemental analysis. All the compounds were evaluated for their possible anticonvulsant activity by Maximal Electroshock Seizure (MES) test and their neurotoxic effects were determined by rotorod test. Majority of the compounds were active in MES tests. Compounds 8f and 8g have shown a significant and protective effect on seizure, when compared with standard drug phenytoin. Compound 8f and 8g without a fluoro group showed anticonvulsant activity in MES test as compared with compound 8a and 8b with fluoro substituents. From this study, it is quite apparent that there are at least three parameters for the activity of anticonvulsant drugs, that is, a lipophilic domain, a distal hydrophobic center and two-electron donor (-C-N-) system.

Series of 2-[4-(2,4-dimethoxy-benzoyl)-phenoxy]-1-[4-(3-piperidin-4-yl-propyl)-piperidin-1-yl]-ethanone derivatives 9 ( a – d ) and 10 ( a – d ) were synthesized in good yield. The synthesized compounds were characterized by 1 H NMR, LC–MS, FTIR and elemental analysis. All the compounds were screened for in vivo wound-healing activity by incision and dead space wound models on Swiss albino rats. Significant wound healing was observed in 10b and 10d treated groups as also the epithelialization of the incision wound was faster with a high rate of wound contraction in these groups. The tensile strength of the incision wound was significantly increased in 10b and 10d compared to the Nitrofurazone, the standard skin ointment. In dead space wound model also the weight of the granulation was higher indicating increase in collagenation. The SAR correlation studies revealed that the thioamide functional linkage and electron withdrawing groups influence the wound-healing activity.

The title compound 1-benzhydryl-4-(4-chloro-2-fluoro-benzenesulfonyl)-piperazine was synthesized, and structure of the product obtained was confirmed by the X-ray diffraction study. The compound C23H22ClFN2O2S crystallizes in the monoclinic crystal class in the space group P21/c with cell parameters a = 9.6180(7) A , b = 12.9670(10) A , c = 19.4020(12) A , β = 114.716(3)°, and Z = 4. The structure has been solved by direct methods and refined to R 1 = 0.0440 for 3877 observed reflections with I > 2σ(I). The structure reveals that the piperazine ring is in a chair conformation. The geometry around the S atom is distorted tetrahedral.

A series of novel diphenyl(piperidin-4-yl)methanol derivatives 10(a–n) were synthesized and characterized by 1H NMR, LC/MS, FTIR, and elemental analyses. All the synthesized compounds were evaluated for cell proliferation by MTT assay. The antiproliferative effects of the synthesized compounds were tested against viable human skin fibroblast cell line and carcinoma cell lines, namely HeLa cells, HT-29 cells, MCF-7 cells, and HepG-2 cells in comparing the positive and negative control. Among the synthesized compounds, (10b) and (10g) have been identified as potent antiproliferative agents.

Several 1-benzhydryl-sulfonyl-4-(3-(piperidin-4-yl)propyl)piperidine derivatives 8(a-j) were prepared by the treatment of substituted benzhydryl chlorides with 4-(3-(piperidin-4-yl)propyl)piperidine followed by N-sulfonation with sulfonyl chlorides in the presence of dry methylene dichloride and triethyl amine. The synthesized compounds were characterized by (1)H-NMR, IR, and elemental analysis. All the synthesized compounds were evaluated in vitro for their efficacy as antimicrobial agents by artificial inoculation technique against standard strains of two important bacterial viz., Xanthomonas axonopodis pv. vesicatoria and Ralstonia solanacearum as well as and two fungal pathogens namely Alternaria solani and Fusarium solani of tomato plants. We have briefly investigated the structure-activity relation studies and reveal that the nature of substitutions on benzhydryl ring and sulfonamide ring influences the antibacterial activity. Among the synthesized new compounds 8b, 8d, 8g, 8h, 8i, and 8j were showed significant potent antimicrobial activities compared to the standard drugs chloramphenicol, mancozeb.

A series of novel 6-fluoro-3-(4-piperidinyl)-1,2-benzisoxazole derivatives 5(a-m) were synthesized with different substituted aromatic/heterocyclic acid chlorides (R-CO-Cl) and characterized by (1)H NMR, LC/MS, FTIR and elemental analyses. All the compounds synthesised were evaluated for their antiproliferative activity by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The antiproliferative effects of the synthesised compounds were tested against viable human skin fibroblast cells and carcinoma cells namely HeLa cells, HT-29 cells, MCF-7 cells, HepG-2 cells by adopting positive and negative control. The importance of the aromatic and heterocyclic moiety was confirmed. From the SAR studies, it reveals that, the substitution at N-terminal of 6-fluoro-3-(4-piperidinyl)-1,2-benzisoxazole by the heterocyclic ring plays a dominant role and was responsible for the antiproliferative activity. Among the synthesized compounds 5a, 5d and 5k have showed potent antiproliferative activity on all the carcinoma cells tested.

The compound, 7-chloro-5-cyclopropyl-9-methyl-10-(2-piperidin-1-yl-ethyl)-5,10-dihydro-4,5,6,10-tetraaza-dibenzo[a, d] cyclohepten-11-one, C22H26N5ClO, crystallizes in the triclinic space group Pī with cell parameters a = 8.918(7) A, b = 9.297(7) A, c = 14.184(8) A, V = 1095.98(1) A3 and Z = 2. The final residual factor R 1 = 0.0451. The structure exhibits intermolecular hydrogen bonds. The 2-piperidin-1-yl-ethyl ring adopts a chair conformation. The starting material used to synthesize the title compound is the intermediate compound of well known anti-HIV drug Nevirapine hence the title compound is having biological importance and hence this crystal structure will helps to structural characterization of the molecule and also for the molecular modeling it will helps for biological study. The title compound 7-chloro-5-cyclopropyl-9-methyl-10-(2-piperidin-1-yl-ethyl)-5,10-dihydro-4,5,6,10-tetraaza-dibenzo[a, d] cyclohepten-11-one was synthesized by condensation of 7-chloro-5-cyclopropyl-9-methyl-5,10-dihydro-4,5,6,10-tetraaza-dibenzo[a, d] cyclohepten-11-one with 1-(2-chloro-ethyl)-piperidine hydrochloride in presence of anhydrous powdered potassium carbonate as base using N,N-dimethyl formamide as solvent and its crystal structure determined. The title compound derived from bioactive molecule and it is also having biological importance hence this crystal structure will helps for the structural characterization and the biological study of the novel molecule.

The title compound 1-benzhydryl-4-(toluene-4-sulfonyl)-piperazine was synthesized and the structure was investigated by X-ray crystallography. The title compound, C24H26N2O2S crystallizes in the monoclinic crystal class in the space group P21/c with cell parameters a = 13.5800(10) A, b = 8.9630(7) A, c = 18.9040(10) A, β = 106.851(3)°, Z = 4 and V = 2202.1(3) A3. The structure has been solved by direct methods and refined to R 1 = 0.0468 for 3174 observed reflections I > 2σ(I). The structure reveals that the piperazine ring is in a chair conformation. The geometry around the S atom is a distorted tetrahedron. The title compound 1-benzhydryl-4-(toluene-4-sulfonyl)-piperazine was synthesized and the structure was investigated by X-ray crystallography. The title compound, C24H26N2O2S crystallizes in the monoclinic crystal class in the space group P21/c with cell parameters a = 13.5800(10) A, b = 8.9630(7) A, c = 18.9040(10) A, β = 106.851(3)°, Z = 4 and V = 2202.1(3) A3. The structure has been solved by direct methods and refined to R 1 = 0.0468 for 3174 observed reflections I > 2σ(I). The structure reveals that the piperazine ring is in a chair conformation. The geometry around the S atom is a distorted tetrahedron.

A series of novel 1-benzhydryl-sulfonyl-piperazine derivatives 3(a-e) were synthesized by nucleophilic substitution reaction of 1-benzhydryl-piperazine with different sulfonyl chlorides and were characterized by 1H NMR, LC/MS, FTIR and elemental analysis. In the present study, the compounds 3(a-e) exhibited in vivo inhibition of Ehrlich ascites tumor (EAT) cell growth and increased the Median Survival Time (MST) and %ILS of EAT bearing mice. Further treatment of derivatives in vivo resulted in reduction of EAT cell number and ascites formation. The efficacy of the derivatives to inhibit the angiogenesis in vivo was evaluated in tumor bearing mice peritoneum and chorio allantoic membrane (CAM) model. The compounds suppressed the blood vessel formation in vivo in mice peritoneum and in CAM. Among the compounds studied, 3e demonstrated highest tumor inhibitory and anti-angiogenic effects against mouse tumor. However, this phenomenon needs detailed investigation.

The title compound, [1-(toluene-4-sulfonyl)-piperidin-4-yl]-methanol was synthesized by the condensation of diphenyl(piperidin-4-yl)methanol with p-toluenesulfonyl chloride in methylene dichloromethane as solvent and triethylamine as the base. The product obtained was characterized by spectroscopic techniques and the structure was investigated by X-ray crystallography. The compound crystallizes in the monoclinic crystal class in the space group P21/c with cell parameters a = 10.2490(13) A˚, b = 11.4710(9) A˚, c = 20.997(3) A˚, β = 116.344(3)°, V = 2212.2(5) A˚3 for Z = 4. The structure reveals that the piperidine ring is in a chair conformation. The geometry around the S atom is comparable with the classic tetrahedral value. The structure exhibits both inter and intramolecular hydrogen bonds of the type O–H · · · O and C–H · · · O.

In the course of structure-activity relationship studies and to explore the antiproliferative effect associated with the hydantoin framework, diversely substituted several diazaspiro hydantoins were synthesized. Variation in the functional group at N-terminal of the hydantoin ring and coupling of different substituted aromatic acids in 4-aminocyclohexanone ring led to three sets of compounds. The antiproliferative effect of the compounds was evaluated in vitro using the MTT colorimetric method against one normal cell line (NDF-103 skin fibroblast cells) and four human cancer cell lines (MCF-7 breast carcinoma cell line, HepG-2 hepatocellular carcinoma cell line, HeLa cervix carcinoma cell line and HT-29 colon carcinoma cell line) for the time period of 24 h. Among the series, some compounds exhibited interesting growth inhibitory effects against all four cell lines. From the SAR studies, it reveals that, the substitution at N-terminal in hydantoin ring plays key role in the antiproliferative activity.

A series of novel 5-(4-methyl-benzylidene)-thiazolidine-2,4-dione derivatives 6 (a-d) and 7 (a-g) were synthesized with different substituted aromatic sulfonyl chlorides (R-SO(2)-Cl) and alkyl halides (R-X) and were characterized by (1)H NMR, LC/MS, FTIR and elemental analyses. All the compounds synthesised were evaluated for their cell antiproliferation activity by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The antiproliferative effects of the synthesised compounds were tested against viable human skin fibroblast cell line and carcinoma cell lines namely HeLa cells, HT-29 cells, MCF-7 cells, HepG-2 cells by adopting positive and negative control. The importance of the nitro group on thiazolidinone moiety was confirmed and it was concluded that the fourth position of the substituted aryl ring plays a dominant role and was responsible for the antiproliferative activity. Among the synthesized compounds only 6a, 7e and 7g have potent antiproliferative activity on all the carcinoma cell lines tested.

The title compound 1-(2-nitro-benzenesulfonyl)-piperidin-4-yl-diphenyl-methanol was synthesized by the condensation of [piperidin-4-yl]-diphenyl-methanol with 2-nitro benzene sulfonylchloride in methylene dichloride as solvent and triethylamine as the base. The product obtained was characterized by spectroscopic techniques and the structure was investigated by X-ray crystallography. The compound crystallizes in the monoclinic crystal class in the space group Pc with cell parameters a = 9.2360(4) A, b = 10.7750(8) A, c = 13.4110(8) A, β = 124.162(4)°, V = 1104.35(12)A3 for Z = 2. The structure reveals that the piperidine ring is in a chair conformation. There is a large discrepancy around the bond angles of the piperidine N atom. The geometry around the S atom is distorted tetrahedron.

The compound 7-chloro-5-cyclopropyl-9-methyl-10-(2-nitro-4-trifluromethyl-phenyl)- 5,10-dihydro-4,5,6,10-tetraaza-dibenzo[a,d]cyclohepten-11-one, C22H15N5O3F3Cl, crystallizes in the monoclinic crystal class under the space group P21/c with cell parameters a = 16.595(7) A, b = 8.775(7) A, c = 14.973(1) A, β = 97.465(4), V = 2161.9(3) A3, Z = 4. The structure was solved by direct methods using SHELXS-97, and refined using SHELXL-97. The final residual factor is R1 = 0.0604 for 4116 reflections and 342 parameters. The molecular structure exhibits intramolecular hydrogen bond of the type C–H · · · O.

The title compound, 1-benzhydryl-4-methanesulfonyl-piperazine, was synthesized by the nucleophilic substitution of 1-benzhydryl-piperazine with methyl sulfonyl chloride. The product obtained was characterized by spectroscopic techniques, and the structure was investigated by X-ray crystallography. The compound crystallizes in the monoclinic crystal class in the space group P21/c with cell parameters a = 9.5820(4) A○, b = 16.8150(12) A○, c = 13.5280(8) A○, β = 127.270(5)°, and V = 1734.5(2)A○ 3 for Z = 4. The structure reveals that the piperazine ring is in a chair conformation. There is a large discrepancy around the bond angles of the piperazine N atoms. The geometry around the S atom is distorted tetrahedral.

1-Benzhydryl-4-phenylmethane sulfonyl piperazine was synthesized from 1-benzhydryl piperazine with phenylmethane sulfonyl chloride. The product obtained was characterized by 1H NMR, MS and IR techniques and finally confirmed by X-ray crystallography. The title compound C24H26N2O2S, M r = 406.53, crystallizes in the orthorhombic crystal class in the space group Pbca with unit cell parameters a = 11.1240(10)A, b = 9.4940(15)A, c = 40.239(4)A, Z = 8 and V = 4249.7(9)A3. The structure was solved by direct methods and refined to R 1=0.0561 for 2,445 reflections with [I > 2 σ(I)]. The piperazine ring adopts a chair conformation. The sulfonyl moiety is in a distorted tetrahedral configuration.

A series of novel 1-benzhydryl-sulfonyl-piperazine derivatives 7(a-e) were designed by a nucleophilic substitution reaction of 1-benzhydryl-piperazine with various sulfonyl chlorides and characterized by 1H nuclear magnetic resonance (NMR), liquid chromatography mass spectrometry (LC/MS), Fourier-transform infrared (FTIR), and elemental analysis. Our research is focused on identifying synthetically occurring chemotherapeutic substances capable of inhibiting, retarding, or reversing the process of multistage carcinogenesis. The title compounds were evaluated for their efficacy in inhibiting MDA-MB-231 breast cancer cell proliferation. Compound 1-benzhydryl-4-(4-tert-butyl-benzenesulfonyl)-piperazine (7d) showed significant inhibitory activity.

1-Benzenesulfonyl-4-benzhydryl-piperazine was synthesized from 1-benzhydryl piperazine with benzenesulfonyl chloride. The title compound, C23H24N2O2S, was synthesized and the structure was investigated by X-ray crystallography. The compound crystallizes in the monoclinic crystal class in the space group P21/c with cell parameters a = 13.2390(10) A, b = 9.1960(7) A, c = 18.5810(16) A, β = 110.873(3)°, and Z = 4. The piperazine ring in the structure is in a chair conformation. The geometry around the S atom is distorted tetrahedral. The structure exhibits an intermolecular hydrogen bond of the type C‒H · O.

The title compound, C13H13N2O3, a hydantoin derivative, crystallized with two molecules (AandB) in an asymmetric unit. In moleculeA, the imidazolidine ring is twisted about the C—N bond involving the spiro C atom, while in moleculeBthis ring is flat (r.m.s. deviation = 0.010 Å). The pyran rings in both molecules have distorted half-chair conformations. The mean plane of the imidazolidine ring is inclined to the aromatic ring of the chroman unit by 79.71 (11)° in moleculeAand 82.83 (12)° in moleculeB. In the crystal, pairs of N—H...O hydrogen bonds link the individual molecules to formA–AandB–Binversion dimers. The dimers are linkedviaN—H...O and C—H...O hydrogen bonds, forming sheets lying parallel to thebcplane,viz.(011). Within the sheets, theAandBmolecules are linked by C—H...π interactions.

In the title compound, C18H13F2NO2, the two rings of the quinoline system are fused almost coaxially, with a dihedral angle between their planes of 2.28 (8)°. The plane of the attached benzene ring is inclined to the plane of the quinoline system by 7.65 (7)°. The carboxylate group attached to the quinoline system is in an antiperiplanar conformation. There is a short intramolecular C—H...O contact involving the carbonyl group. In the crystal, molecules are linkedviaC—H...O hydrogen bonds, forming chains lying in the (1-10) plane.

In the title compound, C15H18N2O2S, the 2,3-dihydro-1-benzothiopyran ring adopts a sofa conformation and the hydantoin ring is twisted with respect to the benzene ring at 78.73 (17)°. In the crystal, pairs of N—H...O hydrogen bonds link the molecules into inversion dimers.

In the title compound, C8H7N3O2S, the dihedral angle between the 1,2,4-triazole ring and the phenyl ring is 82.17 (14)degrees. The geometry around the S atom is distorted tetrahedral. The molecules are linked by intermolecular C-H center dot center dot center dot N and C-H center dot center dot center dot O hydrogen bonds.

To study the structure activity relationship (SAR) on the cytotoxic activity and probe the structural requirement for the potent antitumor activity, a series of novel diazaspiro bicyclo hydantoin derivatives were designed and synthesized. Their structures were confirmed by H-1 NMR, LCMS and IR analyses. The antiproliferative effect of these compounds were determined against human leukemia, K562 (chronic myelogenous leukemia) and CEM (T-cell leukemia) cells using trypan blue and MTT assay, and the SAR associated with the position of N-terminal substituents in diazaspiro bicyclo hydantoin have also been discussed. It has been observed that these compounds displayed strong, moderate and weak cytotoxic activities. Interestingly, compounds having electron withdrawing groups at third and fourth position of the phenyl ring displayed selectively cytotoxic activities to both the cell lines tested with IC50 value lower than 50 mu M. In addition, the cytotoxic activities of the compounds 7(a-o) bearing the substituents at N-3 position of diazaspiro bicyclo hydantoin increases in the order alkene > ester > ether and plays an important role in determining their antitumor activities. The position and number of substituents in benzyl group attached to N-8 of diazaspiro bicyclo hydantoin nucleus interacted selectively with specific targets leading to the difference of biochemical and pharmacological effects.

In order to explore the antiproliferative effect associated with the piperazine framework, several 1-benzhydrylpiperazine derivatives 8(a-d), 9(a-d) and 10(a-h) were synthesized. Variation in the functional group at N-terminal of the piperazine led to three sets of compounds, bearing the sulfonyl, amide and thiourea, respectively. Their chemical structures were confirmed by (1)H NMR, LCMS, IR and elemental analysis. The antiproliferative effect of the compounds were evaluated in vitro using the MTT colorimetric method against one normal cell line (NF-103 skin fibroblast cells) and four human cancer cell lines (MCF-7 breast carcinoma cell line, HepG-2 hepatocellular carcinoma cell line, HeLa cervix carcinoma cell line and HT-29 colon carcinoma cell line) for the time period of 24 h. Among the series, four compounds exhibited interesting growth inhibitory effects against all four cell lines.

A series of novel, potent, and selective muscarinic receptor 1 agonists (M1 receptor agonists) that employ a key N-substituted morpholine Arecoline moiety has been synthesized as part of research effort for the therapy of Alzheimer’s diseases. The ester group of arecoline (which is reported as muscarinic agonist) has been replaced by N-substituted morpholine ring. The structure–activity relationship reveals that the electron donating 4-substituted sulfonyl derivatives (9a, 9b, 9c, and 9e) on the nitrogen atom of the morpholine ring increases the affinity of M1 receptor binding 50- to 80-fold greater than the corresponding arecoline. Other derivatives also showed considerable M1 receptor binding affinity.

Alzheimer's disease (AD) is a neurodegenerative disorder affecting the central nervous system, which is also associated with progressive loss of memory and cognition. The development of numerous structural classes of compounds with different pharmacological profile could be an evolving, promising therapeutic approach for the treatment of AD. Thus, providing a symptomatic treatment for this disease are cholinomimetics with the pharmacological profile of Acetylcholinesterase (AChE) inhibitors. In view of this, we have synthesized novel 3-aryl-N-methyl-1,2,5,6-tetrahydropyridine derivatives 5a-k by Suzuki coupling and screened the efficacy of these derivatives for their AChE inhibitor activity.

In the title compound, C13H14N2O2, the C5ring has an envelope conformation with the C atom adjacent to the quaternary C being the flap. The five atoms comprising the imidazolidine-2,4-dione ring are almost planar (r.m.s. deviation = 0.004 Å). The dihedral angle between the five-membered rings is 89.66 (10)°. In the crystal, inversion-related molecules are connectedvia{...HNCO}2synthons. These are linked into a helical supramolecular chain along [010] by C—H...O interactions.

The title compound was synthesized and the structure was investigated by X-ray crystallography. The compound crystallizes in the monoclinic crystal class in the space group P21/c with cell parameters a = 7.541(4)A, b = 17.958(8)A, c = 8.091(4)A, β = 111.16(4)° and Z = 4. The geometry around the S atom is distorted tetrahedral. The structure exhibits intermolecular hydrogen bonds of the type C-H…O.