24 research outputs found
SU(N) Quantum Hall Skyrmions
We have investigated skyrmions in N-component quantum Hall systems. We find
that SU(N) skyrmions are the lowest energy charged excitations for filling
factors \nu = 1,2,...,N-1 for small enough symmetry breaking terms. N>2
skyrmions can be realized in Si QH systems based on the (110) or (111)
interfaces of Si, or perhaps in Si (100) systems, where the spin and valley
isospin together provide an SU(4)-symmetry, or in multilayer QH systems. We
also present Hartree-Fock results for a phenomenological easy-axis
SU(2)-breaking model appropriate to valley degeneracy.Comment: 5 pages, 2 figure
Synthesis of biologically active novel <i style="">bis</i> Schiff bases, <i style="">bis </i>hydrazone and <i style="">bis </i>guanidine derivatives
1128-1136A number of bis Schiff′s bases 3a-d have been synthesized by condensation of 2,4,8,10 tetraoxaspiro[5,5]undecane 3,9-dipropanamine 1 with furfural, indole-3-aldehyde, 2-acetylpyridine, 4-acetylpyridine and 5a-c by condensation of 1,4-bis (3-aminopropyl) piperazine 4 with indole-3-aldehyde, 2-acetylpyridine, 4-acetylpyridine, in high yields by using microwave irradiation. Bis hydrazone derivatives 8a-c are obtained by condensation of 2,6-diacetylpyridine 7 with various arylsulfonylhydrazides using microwave irradiation. A number of bis guanidine derivatives 11a-j are synthesized by condensation of 1,3-diaminoguanidine monohydrochloride 10 with various aldehydes 9a-c and ketones 9d-j. The structures assigned to these purified compounds i.e 3a-d, 5a-c, 8a-c, and 11a-j, are supported by correct spectral data and elemental analysis. Anti-inflammatory activities of 3b and 11e are comparable to standard drug phenyl butazone. Analgesic activities of 11e and 3b are compared with phenyl butazone and 3b showed better activity then phenyl butazone
Microwave assisted synthesis of indole and furan derivatives possessing good anti-inflammatory and analgesic activity
1848-1854Indole-2-carboxylic acid on condensation with benzene sulfonyl hydrazide and p-toluene sulfonyl hydrazide gives condensation products 1a and 1b. 1H-Tetrazole-5-acetic acid, hydantoin-5-acetic acid, orotic acid, 5-bromo nicotinic acid and indole 2-carboxylic acid have been condensed with furfuryl amine to give corresponding condensation products 2a-e whereas condensation of succinic acid and adipic acid with furfuryl amine gives products 3a and 3b respectively. 3,5-Pyrazole dicarboxlic acid, 4,5-imidazole dicarboxylic acid and 3-carboxy-1,4-dimethyl pyrole-2-acetic acid on condensation with furfuryl amine give compounds 4, 5 and 6. All these compounds i.e. 1a,b, 2a-e, 3a,b, 4, 5 and 6 have been characterized by spectroscopic means and have been screened for anti-inflammatory and analgesic activity. Compounds 2a, and 5 exhibit good anti-inflammatory and 2a, 2c and 5 exhibit good analgesic activity
ChemInform Abstract: Microwave Assisted Synthesis of Indole and Furan Derivatives Possessing Good Antiinflammatory and Analgesic Activity.
1848-1854Indole-2-carboxylic acid on condensation with benzene sulfonyl hydrazide and p-toluene sulfonyl hydrazide gives condensation products 1a and 1b. 1H-Tetrazole-5-acetic acid, hydantoin-5-acetic acid, orotic acid, 5-bromo nicotinic acid and indole 2-carboxylic acid have been condensed with furfuryl amine to give corresponding condensation products 2a-e whereas condensation of succinic acid and adipic acid with furfuryl amine gives products 3a and 3b respectively. 3,5-Pyrazole dicarboxlic acid, 4,5-imidazole dicarboxylic acid and 3-carboxy-1,4-dimethyl pyrole-2-acetic acid on condensation with furfuryl amine give compounds 4, 5 and 6. All these compounds i.e. 1a,b, 2a-e, 3a,b, 4, 5 and 6 have been characterized by spectroscopic means and have been screened for anti-inflammatory and analgesic activity. Compounds 2a, and 5 exhibit good anti-inflammatory and 2a, 2c and 5 exhibit good analgesic activity
Synthesis of biscoupled hemin-thiazoline derivatives and their anticancer activity evaluation
162-167A number of
biscoupled hemin-thiazoline derivatives 3a-i have been synthesized and
screened in vitro against six
human cancer cell lines consisting of lung large (NCIH460), colon
(HT29), breast (MCF7 and MCF7/ADR), prostate (DU 145) and CNS (U251) tumors.
Compound 3e exhibits good anticancer activity against lung large
(NCIH460; GI50 4.3MM), where compound 3g shows good anti
cancer activity against colon (HT29; GI50 0.9 μM), breast
(MCF7; GI50 0.5μM; MCF7/ADR; GI50 1.8μM),
prostate (DU 145; GI50 1.6μM) and CNS (U251; GI50 2.5μM)
tumors
Synthesis and anticancer activity evaluation of some hemin and hematoporphyrin derivatives
388-393Sulphamerazine, sulphadiazine, and
sulphaguanidine are coupled with hemin to give bis coupled products 1a, 1b
and 1c respectively. 3, 4-Diphenyliminothiazoline, sulphamerazine, sulphaacetamide,
sulphathiazole and sulphadiazine on coupling with hematoporphyrin give bis
coupled products 2a, 2b, 2c, 2d and 2e
respectively. Compounds 1a-c and 2a-e have
been screened for anticancer activity
against a small panel of six cancer cell lines consisting of prostate(DU 145),
colon (HT29), melanoma (LOX), breast(MCF7 and MCF7/ADR) and CNS(U251) tumors.
Best GI50 (concentration which inhibits the cell growth by 50%)
values are shown by 2c, 2.2μM(prostate tumor, cell line DU145);
2c 13.0μM(colon tumor, cell
line HT29); 2b, 3.4μM(melanoma
tumor, cell line LOX); 2c, 9.7μM(breast tumor, cell line MCF7); 2a,
3.1μM(breast, tumor, cell line MCF7/ADR) and 1c, 3.4μM(CNS
tumor, cell line U251) respectively. Out of all the compounds reported here GI50
value shown by 2a i.e.3.1μM against breast, tumor (MCF7/ADR) is quite
close to the GI50 value i.e. 1.8μM, of standard drug doxorubicin
Horseradish peroxidase catalyzed and electrochemical oxidations of 2-thiouracil — A comparison
463-468Horseradish peroxidase (type VIII)
catalyzed and electrochemical oxidations of 2-thiouracil have been studied in
phosphate buffer of pH 7.20 (μ==1.0 M) at an ambient
temperature of 25±2°C. The peroxidase catalyzed oxidation has been initiated by
using hydrogen peroxide and electrooxidation carried out at pyrolytic graphite
electrode. The UV-absorbing
intermediates generated in both the
oxidations have been characterized by voltammetry, spectrophotometry and by
kinetics of decay and are found identical. Products of enzymic and
electrochemical oxidations have been characterized by using GCMS stuides. A
tentative redox scheme has been proposed for the enzymic oxidation of
2-thiouracil and compared with that of electrooxidation and has also been found
similar. Thus, it has been concluded that oxidation of 2-thiouracil by enzymic
and electrochemical methods are, in a chemical sense, identical
Synthesis and anti-inflammatory activity evaluation of some sulfonamide and amidine derivatives of 4-aryl-3-(2 or 4-picolyl)-2-imino-4-thiazolines
1076-1082Condensation of 2-
and 4-picolylaminehydrochloride 2a,b
with (un) substituted phenacylthiocyanate 1a-d
gives 4-aryl-3-(2- or 4-picolyl)-2-imino-4-thiazolines 3a-h in moderate yields. Sulfonamide derivatives 4a-h have been synthesized by
condensation of 4-aryl-3-(2- or 4-picolyl)-2-imino-4-thiazolines 3a-h with methanesulfonylchloride in
good yields. Condensation of 2-cyanopyridine with thiazolines 3a, 3e and of 4-cyanopyridine with 3a,
c, e and h gives amidine derivatives 5a,
b and 6a-d respectively. Thiazoline
derivatives 3a-h, sulfonamide
derivatives 4a-h and amidine
derivatives 5a, b; 6a-d are characterized by IR, 1H
NMR, GC-MS spectral data and elemental analysis. Anti-inflammatory activity
evaluation of 3a-h, 4a-d, g-h, 5a,b and 6a-c using carageenan induced paw oedema assay at 50 mg/kg p.o. has
been carried out and compound 6a exhibited
anti-inflammatory activity comparable to standard drug ibuprofen
Synthesis, anti-inflammatory and analgesic activity evaluation of some pyrimidine derivatives
273-281A number of pyrimidine derivatives 1-3, 5-19 have been synthesized by condensation of bis(2-(vinyloxy))ethylamine, cyclopropylamine, N-(2-amino-4-ethoxyphenyl)acetamide, 2-(aminomethyl thiophene), 2-thiophen ethylamine,
2-hydrazinopyridine, 1-aminonaphthalen-2-ol hydrochloride, furfuryl amine, 2-(4-imidazolyl)ethylamine, 2-picolylamine and 4-methoxyl-2-nitroaniline with various isothiocyanatoketones. These compounds have been screened for
anti-inflammatory and analgesic activities. Compounds 10 and 14 have exhibited 40% and 39% anti-inflammatory and compound 11 has showed 75% analgesic activity at 100 mg/kg p.o. respectively