Provided is a production method capable of efficiently producing a reduced coenzyme Q10 Form II crystal. A method for producing reduced coenzyme Q10 crystals comprises warming a mixture of a reduced coenzyme Q10 Form I crystal and a reduced coenzyme Q10 Form II crystal to 32° C. or higher, in the presence of 0.001 to 50 parts by weight of a solvent with respect to 100 parts by total weight of the crystals, so as to increase the content of the reduced coenzyme Q10 Form II crystal. The warming time may be 1 hour or more and less than 14 hours, and after the warming of the mixture in the presence of the solvent, drying may be performed at 45° C. or higher to remove the solvent.

Provided is a production method capable of efficiently producing a reduced coenzyme Q10 Form II crystal. A method for producing reduced coenzyme Q10 crystals comprises warming a mixture of a reduced coenzyme Q10 Form I crystal and a reduced coenzyme Q10 Form II crystal to 32° C. or higher, in the presence of 0.001 to 50 parts by weight of a solvent with respect to 100 parts by total weight of the crystals, so as to increase the content of the reduced coenzyme Q10 Form II crystal. The warming time may be 1 hour or more and less than 14 hours, and after the warming of the mixture in the presence of the solvent, drying may be performed at 45° C. or higher to remove the solvent.

The present invention relates to a process for the di-O-alkylation of a 1,3-diol according to Formula I (I), said process comprising reacting said 1,3-diol with dioxane, an aliphatic or aromatic hydrocarbon solvent, an alkali metal hydroxide, and dimethyl sulphate, in order to obtain a 1,3-diether according to Formula II (II), wherein R.sup.1 and R.sup.2 are each independently a hydrogen atom or a hydrocarbyl group selected from alkyl, alkenyl, aryl, aralkyl, or alkylaryl groups, and one or more combinations thereof. The process according to the invention is an improved process for preparing 1,3-diether, such as 9,9-bis(methoxymethyl)fluorene, in a high yield and/or having a high purity. 9,9-bis(methoxymethyl)fluorene is a compound that is used as an electron donor for Ziegler-Natta catalysts.

##STR00001##

The present invention relates to a process for the di-O-alkylation of a 1,3-diol according to Formula I (I), said process comprising reacting said 1,3-diol with dioxane, an aliphatic or aromatic hydrocarbon solvent, an alkali metal hydroxide, and dimethyl sulphate, in order to obtain a 1,3-diether according to Formula II (II), wherein R.sup.1 and R.sup.2 are each independently a hydrogen atom or a hydrocarbyl group selected from alkyl, alkenyl, aryl, aralkyl, or alkylaryl groups, and one or more combinations thereof. The process according to the invention is an improved process for preparing 1,3-diether, such as 9,9-bis(methoxymethyl)fluorene, in a high yield and/or having a high purity. 9,9-bis(methoxymethyl)fluorene is a compound that is used as an electron donor for Ziegler-Natta catalysts.

##STR00001##

The present invention relates to a stable crystal form, i.e. form A, of 2-tert-butyl-4-methoxyphenol, and to a new preparation method for the 2-tert-butyl-4-methoxyphenol; and the use of the 2-tert-butyl-4-methoxyphenol and the stable crystal form thereof, i.e. form A, in preparing antitumor drugs or immunomodulator drugs. The stable crystal form, i.e. form A, as expressed by a powder X-ray diffraction pattern in an angle of 2θ, using Cu-Kα radiation, has at least 3 absorption peaks selected from the following positions: 6.27±0.10, 6.94±0.10, 12.27±0.10, 13.36±0.10, 14.01±0.10, 14.79±0.10, 15.31±0.10, 17.05±0.10, 18.30±0.10, 19.00±0.10, 20.47±0.10, 20.98±0.10, 22.37±0.10, 23.68±0.10, 24.55±0.10, 25.37±0.10, 30.83±0.10, 33.12±0.10, 40.50±0.10, 42.81±0.10.

The present invention relates to a stable crystal form, i.e. form A, of 2-tert-butyl-4-methoxyphenol, and to a new preparation method for the 2-tert-butyl-4-methoxyphenol; and the use of the 2-tert-butyl-4-methoxyphenol and the stable crystal form thereof, i.e. form A, in preparing antitumor drugs or immunomodulator drugs. The stable crystal form, i.e. form A, as expressed by a powder X-ray diffraction pattern in an angle of 2θ, using Cu-Kα radiation, has at least 3 absorption peaks selected from the following positions: 6.27±0.10, 6.94±0.10, 12.27±0.10, 13.36±0.10, 14.01±0.10, 14.79±0.10, 15.31±0.10, 17.05±0.10, 18.30±0.10, 19.00±0.10, 20.47±0.10, 20.98±0.10, 22.37±0.10, 23.68±0.10, 24.55±0.10, 25.37±0.10, 30.83±0.10, 33.12±0.10, 40.50±0.10, 42.81±0.10.

The present invention relates to a stable crystal form, i.e. form A, of 2-tert-butyl-4-methoxyphenol, and to a new preparation method for the 2-tert-butyl-4-methoxyphenol; and the use of the 2-tert-butyl-4-methoxyphenol and the stable crystal form thereof, i.e. form A, in preparing antitumor drugs or immunomodulator drugs. The stable crystal form, i.e. form A, as expressed by a powder X-ray diffraction pattern in an angle of 2θ, using Cu-Kα radiation, has at least 3 absorption peaks selected from the following positions: 6.27±0.10, 6.94±0.10, 12.27±0.10, 13.36±0.10, 14.01±0.10, 14.79±0.10, 15.31±0.10, 17.05±0.10, 18.30±0.10, 19.00±0.10, 20.47±0.10, 20.98±0.10, 22.37±0.10, 23.68±0.10, 24.55±0.10, 25.37±0.10, 30.83±0.10, 33.12±0.10, 40.50±0.10, 42.81±0.10.

The present generally relates to an improved process for the preparation of dapagliflozin of Formula I or its solvates or co-crystals thereof. The present invention also encompasses the novel intermediates and their use in the preparation of dapagliflozin.

The present generally relates to an improved process for the preparation of dapagliflozin of Formula I or its solvates or co-crystals thereof. The present invention also encompasses the novel intermediates and their use in the preparation of dapagliflozin.

Shown and described are improved processes for the preparation of dapagliflozin of Formula I, ##STR00001##
or its solvates or co-crystals thereof and intermediates and their use in the preparation of dapagliflozin of Formula I or its solvates or co-crystals thereof.