The invention provides a fullerene compound; a lubricant that is for a magnetic recording medium and that contains the fullerene compound; and a magnetic recording medium. The fullerene compound is an ionic liquid that is represented by general formula (1) and is formed from a Bronsted acid (H.sub.n1X) and a Bronsted base ([R.sub.2R.sub.3)N—].sub.m1—R.sub.1); wherein one of the Brønsted acid and the Broønsted base contains a group having a fullerene; and the other contains a perfluoroalkyl chain. ##STR00001##

The invention provides a fullerene compound; a lubricant that is for a magnetic recording medium and that contains the fullerene compound; and a magnetic recording medium. The fullerene compound is an ionic liquid that is represented by general formula (1) and is formed from a Bronsted acid (H.sub.n1X) and a Bronsted base ([R.sub.2R.sub.3)N—].sub.m1—R.sub.1); wherein one of the Brønsted acid and the Broønsted base contains a group having a fullerene; and the other contains a perfluoroalkyl chain. ##STR00001##

Provided are a compound represented by the following General Formula (A1-1), a method for producing the same, and the use of the compound:

##STR00001##

wherein R.sup.5 and R.sup.6 represent a hydrogen atom or an alkyl group, L.sup.1 and L.sup.2 represent an alkylene group having 1 to 6 carbon atoms, Sp.sup.a and Sp.sup.b represent a single bond or a divalent linking group, R.sup.11 and R.sup.21 represent a substituent, and v1 and w1 are an integer of 0 to 4. Further provided that a structure represented by (R.sup.11).sub.v1-benzen ring/cyclopentadiene skeleton/naphthalene ring-(R.sup.21).sub.w1 is not line-symmetrical, where “/” represents that two rings described on left and right sides of the structure are fused.

Provided are a compound represented by the following General Formula (A1-1), a method for producing the same, and the use of the compound:

##STR00001##

wherein R.sup.5 and R.sup.6 represent a hydrogen atom or an alkyl group, L.sup.1 and L.sup.2 represent an alkylene group having 1 to 6 carbon atoms, Sp.sup.a and Sp.sup.b represent a single bond or a divalent linking group, R.sup.11 and R.sup.21 represent a substituent, and v1 and w1 are an integer of 0 to 4. Further provided that a structure represented by (R.sup.11).sub.v1-benzen ring/cyclopentadiene skeleton/naphthalene ring-(R.sup.21).sub.w1 is not line-symmetrical, where “/” represents that two rings described on left and right sides of the structure are fused.

Provided herein are salt and solid forms of (2E,4E)-3-methyl-5-((1S,2S)-2-methyl-2-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydronaphthalen-2-yl)cyclopropyl)penta-2,4-dienoic acid, including a Tris salt form of (2E,4E)-3-methyl-5-((1S,2S)-2-methyl-2-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydronaphthalen-2-yl)cyclopropyl)penta-2,4-dienoic acid, and polymorphs thereof, methods of preparing the compounds, and their uses.

A polyaryl carboxylic fullerene derivative and its use in anti-coronavirus infection are disclosed. Specifically, a compound shown in formula A: fullerene-RR.sub.1R.sub.2R.sub.3R.sub.4R.sub.5 formula A, or a stereoisomer, prodrug, pharmaceutically acceptable salt, or pharmaceutically acceptable solvate of the compound is provided. The compound or a derivative thereof has promising application prospects in anti-coronavirus infection.

A polyaryl carboxylic fullerene derivative and its use in anti-coronavirus infection are disclosed. Specifically, a compound shown in formula A: fullerene-RR.sub.1R.sub.2R.sub.3R.sub.4R.sub.5 formula A, or a stereoisomer, prodrug, pharmaceutically acceptable salt, or pharmaceutically acceptable solvate of the compound is provided. The compound or a derivative thereof has promising application prospects in anti-coronavirus infection.

The invention provides a fullerene compound; a lubricant that is for a magnetic recording medium and that contains the fullerene compound; and a magnetic recording medium. The fullerene compound is an ionic liquid that is represented by general formula (1) and is formed from a Bronsted acid (H.sub.n1X) and a Bronsted base ([R.sub.2R.sub.3)N—].sub.m1—R.sub.1); wherein one of the Brønsted acid and the Broønsted base contains a group having a fullerene; and the other contains a perfluoroalkyl chain.

##STR00001##

The invention provides a fullerene compound; a lubricant that is for a magnetic recording medium and that contains the fullerene compound; and a magnetic recording medium. The fullerene compound is an ionic liquid that is represented by general formula (1) and is formed from a Bronsted acid (H.sub.n1X) and a Bronsted base ([R.sub.2R.sub.3)N—].sub.m1—R.sub.1); wherein one of the Brønsted acid and the Broønsted base contains a group having a fullerene; and the other contains a perfluoroalkyl chain.

##STR00001##

Provided herein are compounds useful for the preparation of compounds that have retinoid-like biological activity. Also provided herein are processes for the preparation of compounds that have retinoid-like biological activity.