A process for the high-yield preparation of p-(R)calix[9-20]arenes.

A process for the high-yield preparation of p-(R)calix[9-20]arenes.

A process for the high-yield preparation of p-(R)calix[9-20]arenes.

The preparation method for the diester structure monomer includes the following steps: dissolving glycolate in a reaction solvent to prepare a glycolate solution; mixing the glycolate solution with triethylamine in a protective atmosphere, and cooling to form a mixture; and keeping the protective atmosphere unchanged, and adding the methacryloyl chloride to the mixture for esterification to generate a diester structure monomer. The diester structure monomer generated by the preparation method for the diester structure monomer has a long diester side chain and a group with a small volume and high acid sensitivity. As a result, a resin synthesized from the diester structure monomer has good adhesive force and film-forming property, high deprotection efficiency and plasticity, and the hardness and brittleness of the resin are improved. Moreover, the prepared diester acid protected structure monomer has the advantages of high yield, low by-product content and easy separation and purification.

The preparation method for the diester structure monomer includes the following steps: dissolving glycolate in a reaction solvent to prepare a glycolate solution; mixing the glycolate solution with triethylamine in a protective atmosphere, and cooling to form a mixture; and keeping the protective atmosphere unchanged, and adding the methacryloyl chloride to the mixture for esterification to generate a diester structure monomer. The diester structure monomer generated by the preparation method for the diester structure monomer has a long diester side chain and a group with a small volume and high acid sensitivity. As a result, a resin synthesized from the diester structure monomer has good adhesive force and film-forming property, high deprotection efficiency and plasticity, and the hardness and brittleness of the resin are improved. Moreover, the prepared diester acid protected structure monomer has the advantages of high yield, low by-product content and easy separation and purification.

The present invention relates to a process for preparing a (1S,2R)-(2-hydroxy-3,5,5-trimethyl-3-cyclopentenyl)methyl carboxylate compound of the following general formula (S,R)-(2), wherein R.sup.1 represents a monovalent hydrocarbon group having 1 to 6 carbon atoms, and a bold wedged bond represents the absolute configuration, and a (1R,2S)-(2-acetoxy-3,5,5-trimethyl-3-cyclopentenyl)methyl carboxylate compound of the following general formula (R,S)-(3), wherein R.sup.1 is as defined above, a hashed wedged bond represents the absolute configuration, and Ac represents an acetyl group, the process comprising: subjecting a (1RS,2SR)-(2-hydroxy-3,5,5-trimethyl-3-cyclopentenyl)methyl carboxylate compound of the following general formula (RS,SR)-(2), wherein R.sup.1 is as defined above, and a hashed unwedged bond represents a relative configuration, to a kinetic resolution reaction with a lipase in the presence of vinyl acetate to obtain the (1S,2R)-(2-hydroxy-3,5,5-trimethyl-3-cyclopentenyl)methyl carboxylate compound ((S,R)-(2)) and the (1R,2S)-(2-acetoxy-3,5,5-trimethyl-3-cyclopentenyl)methyl carboxylate compound ((R,S)-(3)).

##STR00001##

The present invention relates to a process for preparing a (1S,2R)-(2-hydroxy-3,5,5-trimethyl-3-cyclopentenyl)methyl carboxylate compound of the following general formula (S,R)-(2), wherein R.sup.1 represents a monovalent hydrocarbon group having 1 to 6 carbon atoms, and a bold wedged bond represents the absolute configuration, and a (1R,2S)-(2-acetoxy-3,5,5-trimethyl-3-cyclopentenyl)methyl carboxylate compound of the following general formula (R,S)-(3), wherein R.sup.1 is as defined above, a hashed wedged bond represents the absolute configuration, and Ac represents an acetyl group, the process comprising: subjecting a (1RS,2SR)-(2-hydroxy-3,5,5-trimethyl-3-cyclopentenyl)methyl carboxylate compound of the following general formula (RS,SR)-(2), wherein R.sup.1 is as defined above, and a hashed unwedged bond represents a relative configuration, to a kinetic resolution reaction with a lipase in the presence of vinyl acetate to obtain the (1S,2R)-(2-hydroxy-3,5,5-trimethyl-3-cyclopentenyl)methyl carboxylate compound ((S,R)-(2)) and the (1R,2S)-(2-acetoxy-3,5,5-trimethyl-3-cyclopentenyl)methyl carboxylate compound ((R,S)-(3)).

##STR00001##

Disclosed herein is an ophthalmic formulation comprising a compound of formula (I) wherein le is a linear or branched C.sub.9-C.sub.33 alkyl or a linear or branched C.sub.9-C.sub.33 alkenyl with 1 to 4 double bonds; R.sup.2 is a linear or branched C.sub.9-C.sub.19 alkyl or a linear or branched C.sub.9-C.sub.19 alkenyl with 1 to 4 double bonds; and an ophthalmologically acceptable carrier.

Disclosed herein is an ophthalmic formulation comprising a compound of formula (I) wherein le is a linear or branched C.sub.9-C.sub.33 alkyl or a linear or branched C.sub.9-C.sub.33 alkenyl with 1 to 4 double bonds; R.sup.2 is a linear or branched C.sub.9-C.sub.19 alkyl or a linear or branched C.sub.9-C.sub.19 alkenyl with 1 to 4 double bonds; and an ophthalmologically acceptable carrier.

Disclosed herein is an ophthalmic formulation comprising a compound of formula (I) wherein le is a linear or branched C.sub.9-C.sub.33 alkyl or a linear or branched C.sub.9-C.sub.33 alkenyl with 1 to 4 double bonds; R.sup.2 is a linear or branched C.sub.9-C.sub.19 alkyl or a linear or branched C.sub.9-C.sub.19 alkenyl with 1 to 4 double bonds; and an ophthalmologically acceptable carrier.