This invention relates to a process for preparing electron deficient olefins, such as 2-cyanoacrylates, using an acid catalyzed two-step process including a transesterification reaction followed by a Knoevenagel condensation reaction.

Provided are a fluorescent probe, a preparation method therefor and a use thereof. The fluorescent probe responds to viscosity sensitively and specifically, can be used for the specific fluorescence labeling of proteins and can also be used in the quantification, detection or kinetic study of proteins and the imaging of cells, tissues and living bodies.

Provided are a fluorescent probe, a preparation method therefor and a use thereof. The fluorescent probe responds to viscosity sensitively and specifically, can be used for the specific fluorescence labeling of proteins and can also be used in the quantification, detection or kinetic study of proteins and the imaging of cells, tissues and living bodies.

Improved iminium based processes for the production of cyanoacrylates and methylidene malonates wherein the improvement pertains to the presence of acid chlorides and/or acid anhydrides in the reaction mix.

Improved iminium based processes for the production of cyanoacrylates and methylidene malonates wherein the improvement pertains to the presence of acid chlorides and/or acid anhydrides in the reaction mix.

Improved iminium based processes for the production of cyanoacrylates and methylidene malonates wherein the improvement pertains to the presence of acid chlorides and/or acid anhydrides in the reaction mix.

Improved iminium based processes for the production of cyanoacrylates and methylidene malonates wherein the improvement pertains to the presence of acid chlorides and/or acid anhydrides in the reaction mix.

The present invention provides a process for the preparation of Teriflunomide (Formula-I). The present invention describes the synthesis of Teriflunomide without isolating the intermediate Leflunomide. Teriflunomide is prepared from 5-Methyl isoxazole-4-carboxylic acid by converting to its acid chloride and coupling with 4-trifluoromethyl aniline to obtain Leflunomide (which is not isolated) followed by ring opening reaction using aq. Sodium Hydroxide to form Teriflunomide. In other words, the process is telescoped from 5-methylisoxazole-4-carbonyl chloride. ##STR00001##

The present invention provides a process for the preparation of Teriflunomide (Formula-I). The present invention describes the synthesis of Teriflunomide without isolating the intermediate Leflunomide. Teriflunomide is prepared from 5-Methyl isoxazole-4-carboxylic acid by converting to its acid chloride and coupling with 4-trifluoromethyl aniline to obtain Leflunomide (which is not isolated) followed by ring opening reaction using aq. Sodium Hydroxide to form Teriflunomide. In other words, the process is telescoped from 5-methylisoxazole-4-carbonyl chloride. ##STR00001##

The present invention provides a process for the preparation of Teriflunomide (Formula-I). The present invention describes the synthesis of Teriflunomide without isolating the intermediate Leflunomide. Teriflunomide is prepared from 5-Methyl isoxazole-4-carboxylic acid by converting to its acid chloride and coupling with 4-trifluoromethyl aniline to obtain Leflunomide (which is not isolated) followed by ring opening reaction using aq. Sodium Hydroxide to form Teriflunomide. In other words, the process is telescoped from 5-methylisoxazole-4-carbonyl chloride. ##STR00001##