To study the function of GLAST, a glutamate transporter highly expressed in the cerebellar Bergmann astrocytes, the mouse GLAST gene was inactivated. GLAST-deficient mice developed normally and could manage simple coordinated tasks, such as staying on a stationary or a slowly rotating rod, but failed more challenging task such as staying on a quickly rotating rod. Electrophysiological examination revealed that Purkinje cells in the mutant mice remained to be multiply innervated by climbing fibres even at the adult stage. We also found that oedema volumes in the mutant mice increased significantly after cerebellar injury. These results indicate that GLAST plays active roles both in the cerebellar climbing fibre synapse formation and in preventing excitotoxic cerebellar damage after acute brain injury.

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In the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene or 1,5-diazabicyclo[4.3.0]non-5-ene, metal-free phthalocyanine was obtained by heating phthalonitrile in alcohols. Addition of a copper(II) salt in the reaction gave copper phthalocyanine in a good yield.

Heterocycles that contain a trifluoromethyl group are important compounds in agricultural and medicinal chemistry. Therefore, the development of a simple and flexible method for the generation of trifluoromethylated heterocyclic systems has received much attention.[1] We believed that the incorporation of a tertiary a-trifluoromethyl alcohol stereocenter (CF 3 C*(OH)R 1 R 2 ) into heterocycles could provide novel drug candidates with unusual biological activities as a result of the unique properties of the tertiary a-trifluoromethyl alcohol functionality.[2] We first became interested in the development of general methods for the synthesis of oxindoles with a tertiary a-trifluoromethyl alcohol moiety in a chiral environment. Oxindoles with a quaternary stereogenic center, especially spirooxindoles, are of potential medicinal interest owing to the unique biological activities of natural products and man-made compounds that contain such systems.[3] As part of our ongoing studies in medicinal fluorine chemistry, [4] we describe herein the highly enantioselective synthesis of oxindoles 3 with two contiguous asymmetric quaternary carbon atoms, including a tertiary a-trifluoromethyl alcohol center, [5] by an asymmetric direct aldol-type condensation of oxindoles with ethyl 3,3,3-trifluoropyruvate (2) under the catalysis of cinchona alkaloids.[6] The two enantiomeric products (S,S)-3 and (R,R)-3 are accessible selectively in high yields with up to 99 % ee with pseudoenantiomeric cinchona alkaloids (Scheme 1).Trifluoropyruvate is one of the most versatile building blocks for the synthesis of chiral trifluoromethylated compounds. Examples of enantioselective nucleophilic addition to trifluoropyruvate in the Friedel-Crafts reaction, the aldol reaction, the Henry reaction, and the carbonyl-ene reaction under the catalysis of chiral Lewis acids, cinchona alkaloids, or proline derivatives have been reported. [7] However, there is no information available on the use of oxindoles as nucleophiles in the corresponding asymmetric addition reactions. We first attempted the enantioselective aldol-type reaction of 3-methyl-2-oxindole (1 a; R 1 = Me, R 2 = H; Scheme 1) with 2 in the presence of cinchonidine as a catalyst.Cinchonidine was found to be an effective catalyst for the enantioselective Friedel-Crafts reaction of indoles reported by Prakash and co-workers; [7e] however, in the direct aldoltype reaction of 1 a with 2, the adduct 3 a was obtained in 67 % yield with poor diastereoselectivity and 50 % ee (Table 1, entry 1). At best only a slight improvement in the diastereomeric ratio and enantioselectivity was observed with other Scheme 1. Aldol-type reaction of oxindoles 1 with ethyl trifluoropyruvate (2) under the catalysis of cinchona alkaloids.

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