The compound represented by formula (IV) or a salt thereof has an inhibitory action on an abscisic acid receptor. The compound or the salt thereof can be used as a plant growth regulator.

##STR00001##

wherein X is an ethylene group, an ethenylene group or an ethynylene group, R.sup.1 is a hydrogen atom, a phenyl group or a naphthyl group, and the phenyl group and naphthyl group each optionally have a substituent selected from the group consisting of a halogen atom, a hydroxyl group, a C1-6 alkyl group, a C1-6 alkyl group substituted with a halogen atom, a C1-6 alkoxy group, an acetyl group, an amino group, an acetylamino group, a phenyl group and a pentafluorosulfanyl group.

The compound represented by formula (IV) or a salt thereof has an inhibitory action on an abscisic acid receptor. The compound or the salt thereof can be used as a plant growth regulator.

##STR00001##

wherein X is an ethylene group, an ethenylene group or an ethynylene group, R.sup.1 is a hydrogen atom, a phenyl group or a naphthyl group, and the phenyl group and naphthyl group each optionally have a substituent selected from the group consisting of a halogen atom, a hydroxyl group, a C1-6 alkyl group, a C1-6 alkyl group substituted with a halogen atom, a C1-6 alkoxy group, an acetyl group, an amino group, an acetylamino group, a phenyl group and a pentafluorosulfanyl group.

[Problem] To provide a biodegradable compound having a structure decomposed in a cell, lipid particles containing the compound, and a pharmaceutical composition comprising the lipid particles. [Solution] The compound of the embodiment is represented by the formula (1): P[XRYR-Q].sub.2 (1). In the formula, P is an alkyleneoxy having an ether bond, X is a divalent linking group having a tertiary amine structure, R is a divalent linking group, R is a single bond or a C.sub.1 to C.sub.6 alkylene, and Q is a liposoluble vitamin residue, a sterol residue, or a C.sub.12 to C.sub.22 aliphatic hydrocarbon group. The structure of the compound contains at least one biodegradable group. From the compound in combination with other lipids such as a lipid capable of reducing aggregation, lipid particles can be formed. Further, the compound can be used for a pharmaceutical composition to deliver an activator into cells.

A nanosized complex includes a nucleic acid and a compound comprising formula (I):

##STR00001## wherein R.sup.1 is an alkylamino group or a group containing at least one aromatic group; R.sup.2 and R.sup.3 are independently an aliphatic group or hydrophobic group; R.sup.4 and R.sup.5 are independently H, a substituted or unsubstituted alkyl group, an alkenyl group, an acyl group, or an aromatic group, or a polymer, a targeting group, a detectable moiety, or a linker, or a combination thereof, and at least one of R.sup.4 and R.sup.5 includes a retinoid or retinoid derivative that targets and/or binds to an interphotoreceptor retinoid binding protein; a, b, c, and d are independently an integer from 1 to 10; and pharmaceutically acceptable salts thereof.

[Problem]

To provide a biodegradable compound having a structure decomposed in a cell, lipid particles containing the compound, and a pharmaceutical composition comprising the lipid particles.

[Solution]

The compound of the embodiment is represented by the formula (1): P[XRYR-Q].sub.2 (1). In the formula, P is an alkyleneoxy having an ether bond, X is a divalent linking group having a tertiary amine structure, R is a divalent linking group, R is a single bond or a C.sub.1 to C.sub.6 alkylene, and Q is a liposoluble vitamin residue, a sterol residue, or a C.sub.12 to C.sub.22 aliphatic hydrocarbon group. The structure of the compound contains at least one biodegradable group. From the compound in combination with other lipids such as a lipid capable of reducing aggregation, lipid particles can be formed. Further, the compound can be used for a pharmaceutical composition to deliver an activator into cells.

A method for producing derivatives of N-retinoylaminoalkane sulfonic acid, the method comprising providing retinoic acid, chloroformate, aminoalkanesulfonic acid selected from the group consisting of cysteic acid and alkyl ester thereof, cysteinesulfinic acid and alkyl ester thereof, homocysteic acid and alkyl ester thereof, homocysteinesulfinic acid and alkyl esters thereof, taurine and derivatives thereof, and an organic solvent, and a base, mixing said components under substantial absence of oxidizing compounds thereby forming a reaction mixture comprising a liquid phase, wherein the liquid phase is one phase and the derivatives of N-retinoylaminoalkane sulfonic acid are formed in said liquid phase.

A method for producing derivatives of N-retinoylaminoalkane sulfonic acid, the method comprising providing retinoic acid, chloroformate, aminoalkanesulfonic acid selected from the group consisting of cysteic acid and alkyl ester thereof, cysteinesulfinic acid and alkyl ester thereof, homocysteic acid and alkyl ester thereof, homocysteinesulfinic acid and alkyl esters thereof, taurine and derivatives thereof, and an organic solvent, and a base, mixing said components under substantial absence of oxidizing compounds thereby forming a reaction mixture comprising a liquid phase, wherein the liquid phase is one phase and the derivatives of N-retinoylaminoalkane sulfonic acid are formed in said liquid phase.

A method for producing derivatives of N-retinoylaminoalkane sulfonic acid, the method comprising providing retinoic acid, chloroformate, aminoalkanesulfonic acid selected from the group consisting of cysteic acid and alkyl ester thereof, cysteinesulfinic acid and alkyl ester thereof, homocysteic acid and alkyl ester thereof, homocysteinesulfinic acid and alkyl esters thereof, taurine and derivatives thereof, and an organic solvent, and a base, mixing said components under substantial absence of oxidizing compounds thereby forming a reaction mixture comprising a liquid phase, wherein the liquid phase is one phase and the derivatives of N-retinoylaminoalkane sulfonic acid are formed in said liquid phase.

A method for producing derivatives of N-retinoylaminoalkane sulfonic acid, the method comprising providing retinoic acid, chloroformate, aminoalkanesulfonic acid selected from the group consisting of cysteic acid and alkyl ester thereof, cysteinesulfinic acid and alkyl ester thereof, homocysteic acid and alkyl ester thereof, homocysteinesulfinic acid and alkyl esters thereof, taurine and derivatives thereof, and an organic solvent, and a base, mixing said components under substantial absence of oxidizing compounds thereby forming a reaction mixture comprising a liquid phase, wherein the liquid phase is one phase and the derivatives of N-retinoylaminoalkane sulfonic acid are formed in said liquid phase.

A nanosized complex includes a nucleic acid and a compound comprising formula (I): ##STR00001## wherein R.sup.1 is an alkylamino group or a group containing at least one aromatic group; R.sup.2 and R.sup.3 are independently an aliphatic group or hydrophobic group; R.sup.4 and R.sup.5 are independently H, a substituted or unsubstituted alkyl group, an alkenyl group, an acyl group, or an aromatic group, or a polymer, a targeting group, a detectable moiety, or a linker, or a combination thereof, and at least one of R.sup.4 and R.sup.5 includes a retinoid or retinoid derivative that targets and/or binds to an interphotoreceptor retinoid binding protein; a, b, c, and d are independently an integer from 1 to 10; and pharmaceutically acceptable salts thereof.