Pyridinium Salt Photochemistry in a Concise Route for Synthesis of the Trehazolin Aminocyclitol, Trehazolamine
摘要:
A strategy for the concise synthesis of trehazolamine, the aminocyclitol core of the potent trehalase inhibitor trehazolin, has been developed. The methodology takes advantage of photocyclization reaction of 1-methoxyethoxymethyl-3-pivaloxymethylpyridinium perchlorate to generate a bicyclicaziridine intermediate, which is transformed under aziridine ring opening conditions to the key intermediate, 3,5-diacetoxy-3-pivaloxymethyl-4-(N-acetylamino)cyclopentene. In addition, the strategy is used in an enantio-divergent sequence for preparation of the natural (+)-trehazolamine and its unnatural (-)-enantiomer. In this route, the chiral auxiliary containing 1-(tetracetyl-alpha-D-glucosyl)-3-pivaloxymethylpyridinium perchlorate undergoes photocyclization to generate separable, diastereomeric bicyclic-aziridines, which are then independently transformed to enantiomeric 3,5diacetoxy-3-pivaloxymethyl-4-(N-acetylamino)cyclopentenes.
The present invention relates to a novel class of substituted nicotinamides. These compounds can inhibit histone deacetylase and are suitable for use in selectively inducing terminal differentiation, and arresting cell growth and/or apoptosis of neoplastic cells, thereby inhibiting proliferation of such cells. Thus, the compounds of the present invention are useful in treating a patient having a tumor characterized by proliferation of neoplastic cells. The compounds of the invention may also be useful in the prevention and treatment of TRX-mediated diseases, such as autoimmune, allergic and inflammatory diseases, and in the prevention and/or treatment of diseases of the central nervous system (CNS), such as neurodegenerative diseases. The present invention further provides pharmaceutical compositions comprising the compounds of the instant invention and safe dosing regimens of these pharmaceutical compositions, which are easy to follow, and which result in a therapeutically effective amount of these compounds in vivo.
The present invention provides compounds which are useful as safe substitutes for the organotin reagent used in coupling reaction for the oxymethylation of aromatic rings, such as alkoxymethylation or hydroxymethylation, with a palladium catalyst and which can dispense with chromatographic purification with silica gel in the production and are suitable for mass production; and compounds applicable even to the oxymethylation of aromatic ring substrates which do not permit coupling reaction by conventional technique or have low reactivity.
A new method for rapid synthesis of pyridine esters without stirring based on Novozym435 catalysis had been reported, which was from pyridine methanols and vinyl esters. Based on single factor experiment, the optimization of the enzymatic transesterification was received by response surface methodology (RSM). The high yield of 82% was still reached when Novozym435 had been recycled 12 times. Under