The compound according to the present embodiment is represented by the following formula (1):
Q-L-CHR.sub.2(1)
(wherein, Q is a non-cationic aliphatic group that does not contain nitrogen but contains oxy; L is a single bond or an aliphatic group containing no nitrogen; Rs are C.sub.12-C.sub.24 aliphatic group, the same or different; and at least one R contains, in the main chain or side chain thereof, a linking group L.sup.R selected from the group consisting of C(O)O, OC(O), OC(O)O, SC(O), C(O)S, C(O)NH, and NHC(O)).

The compound according to the present embodiment is represented by the following formula (1):
Q-L-CHR.sub.2(1)
(wherein, Q is a non-cationic aliphatic group that does not contain nitrogen but contains oxy; L is a single bond or an aliphatic group containing no nitrogen; Rs are C.sub.12-C.sub.24 aliphatic group, the same or different; and at least one R contains, in the main chain or side chain thereof, a linking group L.sup.R selected from the group consisting of C(O)O, OC(O), OC(O)O, SC(O), C(O)S, C(O)NH, and NHC(O)).

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 CH 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.

Novel substituted N-acetyl-L-cysteine (NAC) derivatives and related compounds and methods of using these compounds for the treatment of diseases and/or conditions, including but not limited to diseases and/or conditions of, or involving, the Central Nervous System (CNS), including schizophrenia adrenoleukodystrophy, mitochondrial diseases (e.g. Leigh syndrome, Alpers' disease, and MELAS), Huntington's disease, trichotillomania, HIV-associated neurocognitive disorder, hypoxic-ischemic encephalopathy, drug craving, and drug addiction.

Novel substituted N-acetyl-L-cysteine (NAC) derivatives and related compounds and methods of using these compounds for the treatment of diseases and/or conditions, including but not limited to diseases and/or conditions of, or involving, the Central Nervous System (CNS), including schizophrenia adrenoleukodystrophy, mitochondrial diseases (e.g. Leigh syndrome, Alpers' disease, and MELAS), Huntington's disease, trichotillomania, HIV-associated neurocognitive disorder, hypoxic-ischemic encephalopathy, drug craving, and drug addiction.

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 invention relates to bimesogenic compounds of formula I ##STR00001##
wherein R.sup.11, R.sup.12, MG.sup.11, MG.sup.12, X.sup.11, X.sup.12 and Sp.sup.1 have the meaning given in claim 1, to the use of bimesogenic compounds of formula l in liquid crystal media and particular to flexoelectric liquid crystal devices comprising a liquid crystal medium according to the present invention.

The invention relates to bimesogenic compounds of formula I ##STR00001##
wherein R.sup.11, R.sup.12, MG.sup.11, MG.sup.12, X.sup.11, X.sup.12 and Sp.sup.1 have the meaning given in claim 1, to the use of bimesogenic compounds of formula l in liquid crystal media and particular to flexoelectric liquid crystal devices comprising a liquid crystal medium according to the present invention.

Novel substituted N-acetyl-L-cysteine (NAC) derivatives and related compounds and methods of using these compounds for the treatment of diseases and/or conditions, including but not limited to diseases and/or conditions of, or involving, the Central Nervous System (CNS), including schizophrenia adrenoleukodystrophy, mitochondrial diseases (e.g. Leigh syndrome, Alpers' disease, and MELAS), Huntington's disease, trichotillomania, HIV-associated neurocognitive disorder, hypoxic-ischemic encephalopathy, drug craving, and drug addiction.