01650nas a2200253 4500008004100000022001400041245011400055210006900169260011000238300001200348490000700360520067200367100002201039700002301061700002101084700002101105700002501126700002401151700002601175700002301201700002401224700002201248856012601270 2014 eng d a1144-054600aCu(II) conjugation along the transformation of a vitamin K-3 derivative to a dinaphthoquinone methide radical0 aCuII conjugation along the transformation of a vitamin K3 deriva aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcJAN a277-2840 v383 a
1,1'-Methide-bi-vitamin K-3 (B) has been isolated as a dinaphthoquinone methide radical (DNQM) by the transformation of 1-imino(acetylhydrazino)-vitamin K-3 (A). The transformation follows a biomimetic activation pathway mediated via Cu(II) ion catalyzed oxidative coupling. Single crystal X-ray and electron spin resonance (ESR) experiments combined with density functional calculations elucidate the ``resonance structure'' of the DNQM radical (B). Fluorescence investigations reveal that DNQM facilitates interaction with the cysteine residue. As compared to the parent substrate, B shows a depletion in the level of GSH, triggering apoptosis in HeLa cells.
1 aBadave, Kirti, D.1 aPatil, Shalaka, S.1 aKhan, Ayesha, A.1 aSrinivas, Darbha1 aButcher, Raymond, J.1 aGonnade, Rajesh, G.1 aPuranik, Vedavati, G.1 aPinjari, Rahul, V.1 aGejji, Shridhar, P.1 aRane, Sandhya, Y. uhttp://library.ncl.res.in/content/cuii-conjugation-along-transformation-vitamin-k-3-derivative-dinaphthoquinone-methide-0