Reactions of an Anionic Gallylene with Azobenzene or Azide Compounds Through C(sp)-H and C(sp)-H Activation.

The activation of inert C-H bonds remains a challenge in current chemistry. Here, we report the excellent reactivity of the anionic gallylene species [LGa:][Na(THF)] (L = [(2,6-PrCH)NC(CH)], ) that allows the selective activation one sp C-H bond of several azobenzene and azide derivatives at ambient temperature, with the transfer of the hydrogen atom to one of the nitrogen atoms. The process leads to the formation of the aryl amido products [LGa-κN,C-PhNN(H)(-R-CH)][Na(solvent)] (, R = H solvent = DME (1,2-Dimethoxyethane); , R = -OMe, solvent = DME; , R = -NMe solvent = THF), [LGa-κN,C-(-CH-CH)NN(H)(-CH-CH)][Na(15-C-5)] () with new Ga-C and Ga-N bonds.

Reactions of Low-Valent Gallium Species with Organic Azides: Formation of Imido-, Azoimido-, and Tetrazene Complexes.

The reactivity of two α-diimine-ligated digallanes, [LGa-GaL] (L = [(2,6-iPrCH)NC(CH)], dpp-dad, ; L = 1,2-[(2,6-iPrCH)NC]CH, dpp-bian, ), and a gallylene, [(L)GaNa(THF)] (), toward organic azides was studied. Reaction of digallane or with trimethylsilyl azide (MeSiN), 2-azido-benzonitrile (2-CNCHN), or tosylazide (TosN) results in imido-bridged complexes, [(L)Ga(μ-NSiMe)Ga(L)] () [(L)Ga(μ-NSiMe)Ga(L)] (), [(L)Ga(μ-2-CNCHN)Ga(L)] (), and [(L)Ga(μ-NTos)Ga(L)] (), with elimination of dinitrogen. Treatment of or with 1-adamantyl azide (1-AdN), on the other hand, affords the unsymmetrical dinuclear complexes [(L)Ga(NAd)(NAd)Ga(L)] () and [(L)Ga(NAd)(NAd)Ga(L)] (), which contain both imido and triazene bridges.

[Synthesis and biological evaluation of nitrate-oleanolic acid hybrids as inhibitors of HepG2 cell apoptosis].

To find novel antihepatitis drugs, a series of nitrate-oleanolic acid (OA) hybrids (10a, 10b, 11a-11e and 12a-12c) were designed and synthesized on the basis of previous studies using OA as lead compound, which is widely found in natural plants and liver-specific metabolism. In the present study, ten novel NO-releasing derivatives of OA were synthesized by connecting nitrate to the OA-3-OH through varying lengths of linkers containing antioxidants which were designed to increase the ability of these target compounds to scavenge free radicals. The structures of these objective compounds were determined by IR, MS, 1H NMR and elemental analysis.

Effects of the extract of a Chinese herb Tripterygium wilfordii hook f on rat pituitary gland.

In China, the ethylacetate extract of the herb Tripterygium wilfordii Hook f (TWEE), containing the major active ingredient triptolide, is often used with favorable effect on rheumatoid arthritis patients, in alternation with the use of prednisone. The mechanism of this therapeutic effect, however, has not been completely delineated. In this study, we studied how TWEE and prednisone affect the pituitary and adrenal glands in rats.

[Basic study of biodegradable controlled release chemotherapy].

This study sought to assess the biocompatibility of P(DA-SA)-Adriamycin, a new controlled-release chemotherapy system, in rabbit brain, and to examine its controlled release effect both in vitro and in vivo and its curative effects in vitro. The reaction of animal brain to the implanted P(DA-SA) or P(DA-SA)-Adriamycin was observed. The controlled-release profiles in phosphate buffer solutions and in rabbit brain were measured by UV spectrometry.