02052nas a2200265   4500008004100000022001400041245015900055210006900214260007300283300001000356490000900366520105300375653001601428653002001444653000801464653002101472653001201493653003201505100002701537700002101564700001901585700002601604700002601630856013001656       2012                        eng d  a0022-286000aSingle crystal X-ray structure of lawsone anion: evidence for coordination of alkali metal ions and formation of naphthosemiquinone radical in basic media0 aSingle crystal Xray structure of lawsone anion evidence for coor  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcFEB  a38-450 v10103 a<p>2-hydroxy-1,4-naphthoquinone; Lawsone (Lw) is a natural compound found in henna leaves. The reaction of lawsone with `Na' metal (Lw-1), CH3COONa (Lw-2), NaOH (Lw-3), KOH (Lw-4), K2CO3 (Lw-5) and Tris(hydroxymethyl)aminomethane (Lw-6) were studied. Red orange solids obtained for Lw-1 to Lw-6 are characterized by Elemental Analysis, FTIR, (HNMR)-H-1 and EPR studies. The results reveal the coordination of alkali metals `Na' and `K' to lawsone anion. The single crystal X-ray structure of Lw-6 was solved and it crystallizes in triclinic space group P-1 with extensive hydrogen bonding network of C-H center dot center dot center dot O, N-H center dot center dot center dot O and O-H center dot center dot center dot O between cations and anions. Polycrystalline powder X-band EPR spectra of Lw-1 to Lw-5 shows signals similar to 2.004 at 133 K, while Lw-6 is EPR silent. The naphthosemiquinone (NSQ) radical formed in Lw-2 to Lw-5, is due to disproportion reaction of catechol and naphthoquinone. (C) 2011 Elsevier B.V. All rights reserved.</p>10a2-Hydroxy-110a4-naphthoquione10aEPR10ahydrogen bonding10aLawsone10aNaphthosemiquinone radicals1 aSalunke-Gawali, Sunita1 aKathawate, Laxmi1 aShinde, Yogesh1 aPuranik, Vedavati, G.1 aWeyhermueller, Thomas  uhttps://library.ncl.res.in/content/single-crystal-x-ray-structure-lawsone-anion-evidence-coordination-alkali-metal-ions-and-002936nas a2200313   4500008004100000022001400041245013900055210006900194260007300263300001200336490000900348520175800357653002402115653001602139653002802155653005502183653001202238653003102250100002102281700002202302700002302324700001702347700002002364700002602384700002602410700002802436700002702464856013102491       2014                        eng d  a0022-286000aReaction between lawsone and aminophenol derivatives: synthesis, characterization, molecular structures and antiproliferative activity0 aReaction between lawsone and aminophenol derivatives synthesis c  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcOCT  a397-4050 v10753 a<p>Reaction between two bioreductive reactants lawsone (2-hydroxy-1,4-napthoquinone) and derivatives 2-aminophenol without catalyst is reported. The reaction between lawsone and 4-chloro-2-aminophenol leads to formation of red colored major product 1A:[2-[(5-chloro-hydroxyphenyl)amino]naphthalene-1,4-dione] and fluorescent orange colored minor compound 1B:[10-chloro-benzo[alpha]phenoxazine-5-one]. Molecular structure of 1A and 1B were determined by single crystal X-ray diffraction. Two mechanisms were proposed to the formation of red 1A and 1B. `Ortho-para' tautomeric equilibrium was observed in DMSO-d(6) solution in 1A, which was revealed by H-1, C-13 NMR and LC-MS studies. Molecules of 1A formed dimers via N-H center dot center dot center dot O interaction and polymeric chain of dimers was formed by OH center dot center dot center dot O interactions. Cl center dot center dot center dot Cl interactions were observed between the polymeric chains of dimers in 1A. Molecules of 1B show Cl center dot center dot center dot N interaction. Antiproliferative properties is studied for 1A-5A compounds (obtained by the reaction of lawsone with 2-amino-4-methylpheno1;2A, 2-aminopheno1;3A, 3-aminophenol;4A and 4-aminophenol;5A) and evaluated against two cancer cell lines, THP1 (human monocytic leukemia cells) and COLO205 (colorectal adenocarcinoma) and one normal cell line, HEK293T (human embryonic kidney). The values of 50% inhibitory concentration (IC50) of compounds 1A-5A was determined using XTT assay. The cytotoxic effects of compounds 2A and 3A were observed against COLO205 and compounds 4A and 5A on THP1 were observed to be higher in comparison to their effect on HEK293T cell lines. (C) 2014 Elsevier B.V. All rights reserved.</p>10aAminonaphthoquinone10aAminophenol10aBenzo[alpha]phenoxazine10aCl center dot center dot center dot N interactions10aLawsone10api-pi stacking interaction1 aKathawate, Laxmi1 aJoshi, Pranya, V.1 aDash, Tapan, Kumar1 aPal, Sanjima1 aNikalje, Milind1 aWeyhermueller, Thomas1 aPuranik, Vedavati, G.1 aKonkimalla, Badireenath1 aSalunke-Gawali, Sunita  uhttps://library.ncl.res.in/content/reaction-between-lawsone-and-aminophenol-derivatives-synthesis-characterization-molecular-0