This invention relates to the use of base-labile protecting groups for stepwise synthesis of polymers including oligomers. One or more monomers that have a base-labile protecting group at one end and a leaving group at the other are used in synthetic cycles comprising deprotection under stronger basic conditions to remove the base-labile protecting group, and coupling with a monomer under weaker basic conditions to elongate the polymer without premature deprotection of the base-labile protecting group. Advantages of the invention include the possibility to shorten the synthetic cycle from three steps in prior art methods to two steps, more efficient deprotection, more efficient coupling, and the use of less harmful and less expensive chemicals. One of the goals for stepwise polymer synthesis is to prepare monodisperse and sequence-defined polymers.

This invention relates to the use of base-labile protecting groups for stepwise synthesis of polymers including oligomers. One or more monomers that have a base-labile protecting group at one end and a leaving group at the other are used in synthetic cycles comprising deprotection under stronger basic conditions to remove the base-labile protecting group, and coupling with a monomer under weaker basic conditions to elongate the polymer without premature deprotection of the base-labile protecting group. Advantages of the invention include the possibility to shorten the synthetic cycle from three steps in prior art methods to two steps, more efficient deprotection, more efficient coupling, and the use of less harmful and less expensive chemicals. One of the goals for stepwise polymer synthesis is to prepare monodisperse and sequence-defined polymers.

The present disclosure relates to heterocyclic compounds, pharmaceutically acceptable salts thereof, and pharmaceutical preparations thereof. Also described herein are compositions and the use of such compounds in methods of treating diseases and conditions mediated by deficient CFTR activity, in particular cystic fibrosis.

The present disclosure relates to heterocyclic compounds, pharmaceutically acceptable salts thereof, and pharmaceutical preparations thereof. Also described herein are compositions and the use of such compounds in methods of treating diseases and conditions mediated by deficient CFTR activity, in particular cystic fibrosis.

Provided are a methane-production inhibitor capable of inhibiting methane production for a long period of time, and a method for inhibiting methane production using the composition. A methane-production inhibitor composition contains one or more compounds selected from compounds represented by formula [I] as an effective ingredient, and a method for inhibiting methane production uses the composition.

##STR00001##

(In formula [I], X represents an —OR.sub.1 group, a hydroxyl group, or a halogen atom, Y represents an —OR.sub.2 group or an —SO.sub.2R.sub.3 group, R.sub.1 represents a benzoyl group, R.sub.2 represents a methylsulfonyl group or a chloromethylsulfonyl group, and R.sub.3 represents a chloromethyl group or a hydroxymethyl group.)

Sugar-derived tetrol, non-ionic amphiphilic amine-esters are prepared facilely and efficaciously in a few steps. The process is initiated by the esterification of a sugar-derived tetrol with a fatty acid chloride, then, undergoing triflate esterification followed by nucleophilic displacement of the aforementioned hydrophilic amine. Each synthetic pathway is efficient and affords modest to high yields of target amphiphiles, which are valorized as practicable surfactant surrogates to petroleum incumbents.

Sugar-derived tetrol, non-ionic amphiphilic amine-esters are prepared facilely and efficaciously in a few steps. The process is initiated by the esterification of a sugar-derived tetrol with a fatty acid chloride, then, undergoing triflate esterification followed by nucleophilic displacement of the aforementioned hydrophilic amine. Each synthetic pathway is efficient and affords modest to high yields of target amphiphiles, which are valorized as practicable surfactant surrogates to petroleum incumbents.

Disclosed herein is a lipid having a net charge at physiological pH, and being covalently attached to a lipid moiety. The lipid moiety comprises a hydrocarbon structure having two or more linked hydrocarbon chains, optionally having cis or trans C═C, at least one of said chains being covalently attached to the head group optionally via the linker region. The hydrocarbon chains are bonded to one another at a branch point at an internal carbon of the chain attached to the linker region, which branch point comprises a functional group having an electronegative atom. The hydrocarbon chains each have between 1 and 40 carbon atoms, wherein the hydrocarbon structure in total comprises between 10 and 150 carbon atoms. Advantageously, the hydrocarbon structure may assume a generally flared shape for enhanced delivery of cargo molecules. Further provided are delivery vehicles comprising the lipids.

Disclosed herein is a lipid having a net charge at physiological pH, and being covalently attached to a lipid moiety. The lipid moiety comprises a hydrocarbon structure having two or more linked hydrocarbon chains, optionally having cis or trans C═C, at least one of said chains being covalently attached to the head group optionally via the linker region. The hydrocarbon chains are bonded to one another at a branch point at an internal carbon of the chain attached to the linker region, which branch point comprises a functional group having an electronegative atom. The hydrocarbon chains each have between 1 and 40 carbon atoms, wherein the hydrocarbon structure in total comprises between 10 and 150 carbon atoms. Advantageously, the hydrocarbon structure may assume a generally flared shape for enhanced delivery of cargo molecules. Further provided are delivery vehicles comprising the lipids.

There is provided a production method of a thiopyranose compound represented by the following Formula (2) by reacting a compound represented by the following Formula (1) with a sulfur compound. ##STR00001##
X represents a leaving group. A represents an oxygen atom or a sulfur atom. Further, each of R.sup.1A to R.sup.4B, R.sup.1B to R.sup.4B, and R.sup.5 represents a hydrogen atom or a specific substituent.