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1-Methyl, 1-(alkoxymethyl) and 1-(trimethylsilylmethyl)benzotriazoles are metallated at the α-carbon. Trapping of the resulting metallated species with chlorotrimethylsilane gives compounds which undergo Peterson olefination even with hindered ketones. In some cases, metallation at the 4-position of the benzotriazole is observed. An exhaustive metallation/silylation sequence gives 4-trimethylsilyl substituted 1-benzotriazoles in good yields.

Photolysis of 1-(1-alkoxy-1-alkenyl)benzotriazoles gives moderate yields of 2-alkoxy-indolenines, which can be hydrolysed to oxindoles. A side reaction leads to the formation of imino-oxetanes. The formation of the 2-alkoxy-indolenines is quite insensitive to steric hindrance at the reacting centres.

A novel method for the synthesis of 1,4- and 1,3,4-substituted quinolinium salts and 1,2,4- and 1,2,3,4-substituted-1,2-dibydroquinolines from N-substituted-N(benzotriazol-1-ylmethyl)aniline derivatives is reported.

Repeated metallation/silylation of 1-methoxymethylbenzotriazole 1 gives a high yield of the 4-tristrimethylsilyl benzotriazole derivative 5 which undergoes a high yielding fluoride-catalysed Peterson olefination reaction to give 1-(4-trimethylsilylbenzotriazolyl)-methoxymethylene adamantane 6b. Photolysis of 6b affords a remarkably strained iminoether 7b which can easily be converted to the corresponding oxindole 9.

Alzheimer's disease (AD) is characterized pathologically by the abundance of senile plaques and neurofibrillary tangles in the brain. We synthesized over 1200 novel gamma-secretase modulator (GSM) compounds that reduced Abeta(42) levels without inhibiting epsilon-site cleavage of APP and Notch, the generation of the APP and Notch intracellular domains, respectively. These compounds also reduced Abeta(40) levels while concomitantly elevating levels of Abeta(38) and Abeta(37). Immobilization of a potent GSM onto an agarose matrix quantitatively recovered Pen-2 and to a lesser degree PS-1 NTFs from cellular extracts. Moreover, oral administration (once daily) of another potent GSM to Tg 2576 transgenic AD mice displayed dose-responsive lowering of plasma and brain Abeta(42); chronic daily administration led to significant reductions in both diffuse and neuritic plaques. These effects were observed in the absence of Notch-related changes (e.g., intestinal proliferation of goblet cells), which are commonly associated with repeated exposure to functional gamma-secretase inhibitors (GSIs).

A Peterson olefination reaction involving 1-trimethylsilanyl-methyl1H-benzotriazole and either adamantanone or acetone, in the presence of n-butyllithium, is used to prepare 1-adamantylidenemethyl- 1H-benzotriazole and 1-(2-methylpropenyl)-1H-benzotriazole respectively. Further treatment of these compounds with n-butyllithium and an electrophile affords a variety of 1-heterosubstituted 1-(1-alkenyl)benzotriazoles. Photolysis of the latter compounds yields products from three competing pathways: cyclisation with C-C bond formation, cyclisation with C-S bond formation and halogen atom transfer

A novel method for the synthesis of 1,4- and 1,3,4-substituted quinolinium salts and 1,2,4- and 1,2,3,4-substituted-1,2-dibydroquinolines from N-substituted-N(benzotriazol-1-ylmethyl)aniline derivatives is reported.

1-Methyl, 1-(alkoxymethyl) and 1-(trimethylsilylmethyl)benzotriazoles are metallated at the α-carbon. Trapping of the resulting metallated species with chlorotrimethylsilane gives compounds which undergo Peterson olefination even with hindered ketones. In some cases, metallation at the 4-position of the benzotriazole is observed. An exhaustive metallation/silylation sequence gives 4-trimethylsilyl substituted 1-benzotriazoles in good yields.

A Peterson olefination reaction involving 1-trimethylsilanyl-methyl1H-benzotriazole and either adamantanone or acetone, in the presence of n-butyllithium, is used to prepare 1-adamantylidenemethyl- 1H-benzotriazole and 1-(2-methylpropenyl)-1H-benzotriazole respectively. Further treatment of these compounds with n-butyllithium and an electrophile affords a variety of 1-heterosubstituted 1-(1-alkenyl)benzotriazoles. Photolysis of the latter compounds yields products from three competing pathways: cyclisation with C-C bond formation, cyclisation with C-S bond formation and halogen atom transfer