The invention relates to a thermal conversion vessel (200) used during amidification step of acetone cyanohydrin (ACH), in the industrial process for production of a methyl methacrylate (MMA) or methacrylic acid (MAA). The thermal conversion vessel (200) is used for converting an hydrolysis mixture of α-hydroxyisobutyramide (HIBAM), α-sulfatoisobutyramide (SIBAM), 2-methacrylamide (MACRYDE) and methacrylique acid (MAA), into a mixture of 2-methacrylamide (MACRYDE). It comprises:—at least one compartment (C1, C2, C3, . . . Ci) comprising an inner wall (206a, 206b, . . . 206i) separating said compartment into two communicating parts (C1a, C1b) by a passage provided between the bottom of said vessel and said inner wall,—said compartment having a space above said inner wall, for separating gas phase from liquid phase during thermal conversion,—said compartment being connected to an outlet valve (204a, 204b, . . . 204i). Such vessel allows obtaining a high yield thermal conversion in very safe conditions.

The invention relates to a thermal conversion vessel (200) used during amidification step of acetone cyanohydrin (ACH), in the industrial process for production of a methyl methacrylate (MMA) or methacrylic acid (MAA). The thermal conversion vessel (200) is used for converting an hydrolysis mixture of α-hydroxyisobutyramide (HIBAM), α-sulfatoisobutyramide (SIBAM), 2-methacrylamide (MACRYDE) and methacrylique acid (MAA), into a mixture of 2-methacrylamide (MACRYDE). It comprises:—at least one compartment (C1, C2, C3, . . . Ci) comprising an inner wall (206a, 206b, . . . 206i) separating said compartment into two communicating parts (C1a, C1b) by a passage provided between the bottom of said vessel and said inner wall,—said compartment having a space above said inner wall, for separating gas phase from liquid phase during thermal conversion,—said compartment being connected to an outlet valve (204a, 204b, . . . 204i). Such vessel allows obtaining a high yield thermal conversion in very safe conditions.

The present invention relates to a cationic lipid having one or more biodegradable groups located in a lipidic moiety (e.g., a hydrophobic chain) of the cationic lipid. These cationic lipids may be incorporated into a lipid particle for delivering an active agent, such as a nucleic acid. The invention also relates to lipid particles comprising a neutral lipid, a lipid capable of reducing aggregation, a cationic lipid of the present invention, and optionally, a sterol. The lipid particle may further include a therapeutic agent such as a nucleic acid.

The present invention relates to a cationic lipid having one or more biodegradable groups located in a lipidic moiety (e.g., a hydrophobic chain) of the cationic lipid. These cationic lipids may be incorporated into a lipid particle for delivering an active agent, such as a nucleic acid. The invention also relates to lipid particles comprising a neutral lipid, a lipid capable of reducing aggregation, a cationic lipid of the present invention, and optionally, a sterol. The lipid particle may further include a therapeutic agent such as a nucleic acid.

Disclosed herein are secondary amine compounds that inhibit tRNA synthetase. The compounds of the invention are useful in inhibiting tRNA synthetase in Gram-negative bacteria and are useful in killing Gram-negative bacteria. The secondary amine compounds of the invention are also useful in the treatment of tuberculosis.

The present invention relates to a cationic lipid having one or more biodegradable groups located in a lipidic moiety (e.g., a hydrophobic chain) of the cationic lipid. These cationic lipids may be incorporated into a lipid particle for delivering an active agent, such as a nucleic acid. The invention also relates to lipid particles comprising a neutral lipid, a lipid capable of reducing aggregation, a cationic lipid of the present invention, and optionally, a sterol. The lipid particle may further include a therapeutic agent such as a nucleic acid.

The present invention relates to a cationic lipid having one or more biodegradable groups located in a lipidic moiety (e.g., a hydrophobic chain) of the cationic lipid. These cationic lipids may be incorporated into a lipid particle for delivering an active agent, such as a nucleic acid. The invention also relates to lipid particles comprising a neutral lipid, a lipid capable of reducing aggregation, a cationic lipid of the present invention, and optionally, a sterol. The lipid particle may further include a therapeutic agent such as a nucleic acid.

The present invention relates to a novel pseudoceramide compound, and more particularly, to a novel pseudoceramide compound represented by formula 1 and having skin moisturizing and barrier function characteristics, and a skin topical composition comprising the pseudoceramide compound:

##STR00001##

wherein R.sub.1 represents a linear C12-C18 alkyl group and has at least one double bond, and R.sub.2 represents a linear C12-C22 alkyl group and has a double bond.

The present invention relates to a novel pseudoceramide compound, and more particularly, to a novel pseudoceramide compound represented by formula 1 and having skin moisturizing and barrier function characteristics, and a skin topical composition comprising the pseudoceramide compound:

##STR00001##

wherein R.sub.1 represents a linear C12-C18 alkyl group and has at least one double bond, and R.sub.2 represents a linear C12-C22 alkyl group and has a double bond.

A method for esterification of one or more carboxylic acid groups in a compound containing one or more carboxylic acid groups wherein the esterification reagent is a diazo-compound of formula:

##STR00001##

wherein the R.sub.1 and R.sub.2 groups of the diazo compound are selected such that the corresponding organic compound of formula:

##STR00002##

exhibits a —C—H pKa value between 18 and 29 as measured in DMSO. Specific reagents and methods for esterification are provided. The esterification reagents provided exhibit high selectivity for esterification of carboxylic acid groups over reaction with amine, alcohol or thiol groups in the compound containing one or more carboxylic acid groups. The method can be used to selectively esterify carboxylic acid groups in peptides or proteins.