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Novel Derivatives (novel + derivative)
Selected AbstractsSynthesis, Crystal Structure and Anticancer Activity of Novel Derivatives of Ethyl 1-(4-Oxo-8-aryl-4,6,7,8-tetrahydroimidazo[2,1-c] [1,2,4]triazin-3-yl)formate.CHEMINFORM, Issue 38 2006Krzysztof Sztanke Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Novel Derivatives of the Benzo[b][1,6]naphthyridine System.CHEMINFORM, Issue 31 2006Leslie W. Deady Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Synthesis of Novel Derivatives of 2-(Azolylimino)thiazoline.CHEMINFORM, Issue 34 2005O. S. Eltsov Abstract For Abstract see ChemInform Abstract in Full Text. [source] ChemInform Abstract: Synthesis of Novel Derivatives of 2-(p-Aminobenzenesulfamido)-4,6-dimethylpyrimidine.CHEMINFORM, Issue 35 2001E. G. Mesropyan Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Substituted 1,3,2,4-benzodithiadiazines: Novel derivatives, by-products, and intermediates,HETEROATOM CHEMISTRY, Issue 7 2001Alexander Yu. The synthesis of the title compounds 1 by 1:1 condensation of ArNSNSiMe3 2 with SCl2 followed by intramolecular ortho-cyclization of each [ArNSNSCl] intermediate is complicated by further reaction of 1 with SCl2 to give Herz salts 3. With the 2:SCl2 ratio of 2:1, the formation of by-products 3 is reduced and novel compounds 1 are accessible. With ortho-I containing starting material 2j, the parent compound 1s is obtained as the result of an unexpected I, not H, substitution. The rate of the 1 + SCl2 reaction depends upon a substituent's position, and the minor 8-R isomers 1l,p (R = Br, I) are isolated for the first time from mixtures with the major 6-R isomers due to reduced reactivity toward SCl2. The synthesized compounds 1,3 are characterized by multinuclear (including nitrogen) NMR and X-ray crystallography. According to the X-ray diffraction data, 1j (6-Br) and 1k (7-Br) derivatives are planar, whereas 1i (5-Br) and 1l (8-Br) are bent along the S1···N4 line by ,5° and ,4°, respectively, and the 1r (7-OCH3) derivative is planar in contrast to the known 5-OCH3 isomer, which possesses a significantly folded heterocycle. The distortion of the planar geometry of some compounds 1 is interpreted in terms of a pseudo-Jahn-Teller effect as the result of ,-highest occupied molecular orbital (HOMO) ,*-(LUMO) lowest unoccupied molecular orbital + 1 mixing in a planar conformation. The 2p compound is the first structurally defined Ar,N = S = N,SiMe3 azathiene. The compound Ar,N = S = N,S,NH-Ar 6 modeling the aforementioned intermediate has been isolated and structurally characterized. We describe the attempts to synthesize compounds 1 from 2-aminobenzenethiols and (SN)4 and from salts 3 and Me3SiN3, and we discuss the reaction pathways. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:563,576, 2001 [source] Novel derivatives of the benzo[b][1,6]naphthyridine systemJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 2 2006Leslie W. Deady An efficient synthesis of 2-hydroxy-6-methylbenzo[b][1,6]naphthyridin-1(2H)-one was devised. The hydroxy group was alkylated, acylated and replaced by hydrogen. Electrophilic nitration, bromination and chlorosulfonation occurred readily in the 4-position. From the last, various sulfonamide derivatives were prepared. A selection of the products was screened by the National Cancer Institute. Cytotoxicities were generally low. [source] CR229, a novel derivative of ,-carbolin-1-one, induces cell cycle arrest and apoptosis in HeLa cells via p53 activationCANCER SCIENCE, Issue 9 2007Min Kyoung Kim In the course of screening for novel anticancer compounds, CR229 (6-Bromo-2,3,4,9-tetrahydro-carbolin-1-one), a novel derivative of ,-carbolin-1-one, was generated as a new scaffold candidate. For the first time, the authors demonstrate that CR229 inhibited the growth of HeLa cells by the induction of cell cycle arrest and apoptosis. Analysis of flow cytometry and western blots of HeLa cells treated with 2.5 µM CR229 revealed an appreciable cell cycle arrest in the G1, G2/M phase and apoptotic induction via the p53 -dependent pathway. Furthermore, the release of cytochrome c from mitochondria was detected using confocal microscopy in HeLa cells treated with CR229. Accordingly, these data demonstrate that the anticancer activity of CR229 is associated with: (i) the down-regulation of cyclins and cyclin-dependent kinase; (ii) the induction of p53, p21, and p16; and (iii) the activation of caspase-3. (Cancer Sci 2007; 98: 1402,1407) [source] The generation of nisin variants with enhanced activity against specific Gram-positive pathogensMOLECULAR MICROBIOLOGY, Issue 1 2008Des Field Summary Nisin is the prototype of the lantibiotic group of antimicrobial peptides. It exhibits broad spectrum inhibition of Gram-positive bacteria including important food pathogens and clinically relevant antibiotic-resistant bacteria. Significantly, the gene-encoded nature of nisin means that it can be subjected to gene-based bioengineering to generate novel derivatives. Here, we take advantage of this to generate the largest bank of randomly mutated nisin derivatives reported to date, with the ultimate aim of identifying variants with enhanced bioactivity. This approach led to the identification of a nisin-producing strain with enhanced bioactivity against the mastitic pathogen Streptococcus agalactiae resulting from an amino acid change in the hinge region of the peptide (K22T). Prompted by this discovery, site-directed and site-saturation mutagenesis of the hinge region residues was employed, resulting in the identification of additional derivatives, most notably N20P, M21V and K22S, with enhanced bioactivity and specific activity against Gram-positive pathogens including Listeria monocytogenes and/or Staphylococcus aureus. The identification of these derivatives represents a major step forward in the bioengineering of nisin, and lantibiotics in general, and confirms that peptide engineering can deliver derivatives with enhanced antimicrobial activity against specific problematic spoilage and pathogenic microbes or against Gram-positive bacteria in general. [source] S- Thiazolinyl (STaz) Glycosides as Versatile Building Blocks for Convergent Selective, Chemoselective, and Orthogonal Oligosaccharide SynthesisCHEMISTRY - A EUROPEAN JOURNAL, Issue 25 2006Papapida Pornsuriyasak Abstract In the aim of developing new procedures for efficient oligosaccharide assembly, a range of S- thiazolinyl (STaz) glycosides have been synthesized. These novel derivatives were evaluated against a variety of reaction conditions and were shown to be capable of being chemoselectively activated in the armed,disarmed fashion. Moreover, the S- thiazolinyl moiety exhibited a remarkable propensity for selective activation over other common leaving groups. Conversely, a variety of leaving groups could be selectively activated over the STaz moiety, which, in turn, allowed STaz/S- ethyl and STaz/S- phenyl orthogonal approaches. To demonstrate versatility of novel STaz derivatives, a number of oligosaccharide targets have been synthesized in a convergent selective, orthogonal, and chemoselective fashion. [source] Enantioselective Fluorescent Sensors for N -Boc-Protected Amino Acid Anions Based on BINOLCHINESE JOURNAL OF CHEMISTRY, Issue 5 2010Kuoxi Xu Abstract The four novel derivatives of BINOL have been prepared and the structures of these compounds characterized by IR, MS, 1H and 13C NMR spectroscopy and elemental analysis. The enantioselective recognition of these receptors has been studied by fluorescence titration and 1H NMR spectroscopy. The receptors exhibited different chiral recognition abilities towards N -Boc-protected amino acid anions and formed 1:1 complexes between host and guest. Receptor s exhibit excellent enantioselective fluorescent recognition ability towards the amino acid derivatives. [source] | ||||||||||||||||||||||