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51.
Zhong-Lin Lu Xiao-Sheng Yang Rui-Yao Wang Hoong-Kun Fun Suchada Chantrapromma 《Polyhedron》2009,28(13):2565-2570
Three pyridine coordinated cyclopalladated complexes: (S)-chloro{2-[2-(4-tert-butyl)oxazolinyl]phenyl-C,N}(4-R-pyridine)palladium(II) (R = H, 2; R = CF3, 3; R = NMe2, 4), have been synthesized and structurally characterized. While the crystal structure shows that 2 has a normal N,N-trans-conformation in the coordination sphere of palladium(II), 3 and 4 exhibit uncommon N,N-cis-conformations. From 1H NMR measurements, the major coordination isomer in deuterated chloroform solution is N,N-trans configuration for three palladacycles. It was found that the three complexes catalyze effectively the methanolysis of the PS pesticides including chiral thiophosphates but show different activity depending on the substituents of co-coordinated pyridine ring in 2–4. 相似文献
52.
2,6-Diaminopyridine is found to be a simple fluorescent sensor for theobromine and its diacetyl derivative 2 also effectively binds theobromine. The receptor-binding sites are based on the co-operative hydrogen-bonding abilities of secondary amides. An unprecedented hydrogen-bonded self-organised cyclic tetrameric supramolecular network is shown for one such small molecule 2 containing one heterocyclic ring in contrast to the binuclear substrates like guanine or pterin which usually form cyclic tetrameric structures. 相似文献
53.
Suchada Kongkiatkamon Kittipong Booranasophone Apichat Tongtaksin Valailuck Kiatthanakorn Dinesh Rokaya 《Molecules (Basel, Switzerland)》2021,26(17)
Recently, translucent zirconia has become the most prevalent material used as a restorative material. This study aimed to compare the crown fracture load of the four most common different translucent zirconia brands available in the market at 1.5 mm thickness. Standardized tooth preparations for a full ceramic crown were designed digitally with software (AutoCAD) by placing a 1.0 mm chamfer margin and 1.5 mm occluso-cervical curvature for the crown sample manufacturing. Stylized crowns were chosen to control the thickness of the crown. The axial and occlusal thickness were standardized to 1.5 mm thickness except at the central pit, which was 1.3 mm thick. The STL file for the tooth dies was prepared using software (3Shape TRIOS® Patient Monitoring, Copenhagen, Denmark). The tooth dies were printed with a resin material (NextDent Model 2.0, Vertex-Dental B.V., Soesterberg, The Netherlands) using a 3D printing software (3D Sprint® Client Version 3.0.0.2494) from a 3D printer (NextDent™ 5100, Vertex-Dental B.V., Soesterberg, The Netherlands). The printing layer thickness was 50 µm. Then, a total of twenty-eight (N = 28) stylized crowns were milled out of AmannGirrbach (Amann Girrbach GmbH, Pforzheim, Germany) (n = 7), Cercon HT (Dentsply Sirona, Bensheim, Germany) (n = 7), Cercon XT (Dentsply Sirona, Bensheim, Germany) (n = 7), and Vita YZ XT (Zahnfabrik, Bäd Sackingen, Germany) (n = 7). Following sintering the crowns, sandblasting was performed and they were bonded to the tooth dies with the resin cement (RelyX U-200, 3M ESPE, Seefeld, Germany) and permitted to self-cure under finger pressure for 6 min. The crowns were loaded on the occlusal surface in a universal testing machine (MTS Centurion) with a stainless-steel ball indenter (7 mm radius) with a loading rate of 1 mm/min to contact the stylized crowns on each of the four cusps until failure. A rubber sheet (1.5 mm thickness) was positioned between the crown and indenter, which helped with the load distribution. Statistical analysis was done using SPSS version 20 (IBM Company, Chicago, USA). The fracture loads were analyzed using Dunnett’s T3 test, and the number of cracks was analyzed using the Mann–Whitney U test among the groups. The significant level was set at p value = 0.05. The mean fracture loads were 3086.54 ± 441.74 N, 4804.94 ± 70.12 N, 3317.76 ± 199.80 N, and 2921.87 ± 349.67 N for AmannGirrbac, Cercon HT, Cercon XT, and Vita YZ XT, respectively. The mean fracture loads for the surfaces with the greatest number of cracks (excluding the occlusal surfaces) were on the lingual surface for AmannGirrbach and Cercon HT, on the distal and mesial for Cercon XT, and on the buccal for Vita YZ XT. We found that the AmannGirrbach had the most overall cracks. Cercon XT had the greatest number of occlusal cracks and appeared to be the most shattered. Cercon HT had the least number of cracks. In conclusion, Cercon HT presented the best strength properties, the highest fracture load, and no visible cracks. AmannGirrbach presented the lowest strength properties. 相似文献
54.
Shyamaprosad Goswami Subrata Jana Anita Hazra Hoong-Kun Fun Suchada Chantrapromma 《Supramolecular chemistry》2013,25(5):495-500
The non-covalent synthesis of ionic and molecular complexes of substituted 2-aminopyrimidines with benzoic acid in crystalline solid phase is reported. The nature of supramolecular architecture varied with the substituents in the 2-aminopyrimidine ring. Two complexes have been synthesised from two differently substituted 2-aminopyrimidines and benzoic acid. In one case, proton transfer takes place and an ionic organic salt is formed, whereas in the other, there is no proton transfer and a hydrogen-bonded molecular complex is formed. 相似文献
55.
Wen-Yong Gao Chantana Boonyarat Pitchayakarn Takomthong Kusawadee Plekratoke Yoshihiro Hayakawa Chavi Yenjai Rawiwun Kaewamatawong Suchada Chaiwiwatrakul Pornthip Waiwut 《Molecules (Basel, Switzerland)》2022,27(12)
The present study aimed to investigate the effect of acridone alkaloids on cancer cell lines and elucidate the underlying molecular mechanisms. The ten acridone alkaloids from Atalantia monophyla were screened for cytotoxicity against LNCaP cell lines by a WST-8 assay. Then, the most potential acridone, buxifoliadine E, was evaluated on four types of cancer cells, namely prostate cancer (LNCaP), neuroblastoma (SH SY5Y), hepatoblastoma (HepG2), and colorectal cancer (HT29). The results showed that buxifoliadine E was able to significantly inhibit the proliferation of all four types of cancer cells, having the most potent cytotoxicity against the HepG2 cell line. Western blotting analysis was performed to assess the expression of signaling proteins in the cancer cells. In HepG2 cells, buxifoliadine E induced changes in the levels of Bid as well as cleaved caspase-3 and Bax through MAPKs, including Erk and p38. Moreover, the binding interaction between buxifoliadine E and Erk was investigated by using the Autodock 4.2.6 and Discovery Studio programs. The result showed that buxifoliadine E bound at the ATP-binding site, located at the interface between the N- and C-terminal lobes of Erk2. The results of this study indicate that buxifoliadine E suppressed cancer cell proliferation by inhibiting the Erk pathway. 相似文献
56.
Anwar Usman Ibrahim Abdul Razak Hoong‐Kun Fun Suchada Chantrapromma Bao‐Guo Zhao Jian‐Hua Xu 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o57-o58
In the title compound, C26H22O4, the pyranone ring adopts a twisted boat conformation, while the cyclohexane ring is close to an envelope conformation. The dihedral angle between the mean planes of the coumarin and naphthalene systems is 78.8 (1)°. The attached phenyl ring is in an equatorial position with respect to the cyclohexane ring. 相似文献
57.
58.
Suchada Chantrapromma Anwar Usman Hoong‐Kun Fun 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(11):m531-m533
In the title compound [systematic name: triaqua(1,4,7,10,13,16‐hexaoxacyclooctadecane‐κ6O)(2‐nitrophenolato‐κO)barium(II)–aqua(1,4,7,10,13,16‐hexaoxacyclooctadecane‐κ6O)‐ bis(2‐nitrophenolato‐κ2O,O′)barium(II)–2‐nitrophenolate (1/1/1)], [Ba(C12H24O6)(C6H4NO3)(H2O)3][Ba(C12H24O6)(C6H4NO3)2(H2O)](C6H4NO3), the two BaII atoms encapsulated by the 18‐crown‐6 rings have different coordinations. Although both BaII atoms are coordinated to the six O atoms of the crowns, in the neutral moiety, the BaII atom is coordinated to one terminal O atom from a water molecule, two phenolate O atoms and two nitro‐group O atoms, while in the cationic moiety, the BaII atom is coordinated to three terminal O atoms from water molecules and one phenolate O atom. Both the crowns are eclipsed and translated along the b direction. In the asymmetric unit, the three components are interconnected by four O—H?O interactions. The packing is stabilized by two intermolecular C—H?O interactions and by one O—H?O interaction. 相似文献
59.
Orapun YodsaoueChatchanok Karalai Chanita PonglimanontSupinya Tewtrakul Suchada Chantrapromma 《Tetrahedron》2011,67(36):6838-6846
Bioactivity-guided isolation and purification of the dichloromethane extract from the roots of Caesalpinia pulcherrima yielded 15 new cassane-type diterpenes, named pulcherrins D-R (1-15) together with eight known compounds. The structures of the new metabolites were determined on the basis of spectroscopic analyses including 1D- and 2D-NMR and mass spectroscopy. The anti-inflammatory activity of isolated compounds was investigated with the lipopolysaccharide (LPS)-induced murine macrophage RAW 264.7 cell lines. Compounds 8, 9, 11-15, and 17-23 showed potent NO inhibitory activity. 相似文献
60.
Suchada Chantrapromma Anwar Usman Hoong‐Kun Fun Bo‐Long Poh Chatchanok Karalai 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(9):o589-o590
In the title ternary complex, C10H9N2+·C7H3N2O6?·C7H4N2O6, the pyridinium cation adopts the role of the donor in an intermolecular N—H?O hydrogen‐bonding interaction with the carboxylate group of the 3,5‐dinitrobenzoate anion. The molecules of the ternary complex form molecular ribbons perpendicular to the b direction, which are stabilized by one N—H?O, one O—H?O and five C—H?O intermolecular hydrogen bonds. The ribbons are further interconnected by three intermolecular C—H?O hydrogen bonds into a three‐dimensional network. 相似文献