A process for preparing a compound of formula

##STR00001##

including oxidizing the triphenylmethane sulfone of formula (V) with a quinone chosen from 1,4-benzoquinone, 1,2-benzoquinone, a di(C.sub.1-C.sub.4)alkyl-1,4-benzoquinone, a di(C.sub.1-C.sub.4)alkyl-1,2-benzoquinone, a mono(C.sub.1-C.sub.4)alkyl-1,4-benzoquinone and a mono(C.sub.1-C.sub.4)alkyl-1,2-benzoquinone. A crystalline form of patent blue, sodium salt, can be achieved.

The present disclosure relates to substituted hydroxystilbene compounds and derivatives, specifically 2-substituted hydroxystilbene compounds and derivatives, the synthesis of such compounds and their use in therapy.

The present disclosure relates to substituted hydroxystilbene compounds and derivatives, specifically 2-substituted hydroxystilbene compounds and derivatives, the synthesis of such compounds and their use in therapy.

The invention provides synthetic processes and synthetic intermediate compounds that can be used to prepare therapeutic conjugates. The invention also provides methods for treating HBV and/or HDV infection in a human by administering a therapeutic conjugate prepared by the synthetic methods of the invention.

The invention provides synthetic processes and synthetic intermediate compounds that can be used to prepare therapeutic conjugates. The invention also provides methods for treating HBV and/or HDV infection in a human by administering a therapeutic conjugate prepared by the synthetic methods of the invention.

A method for producing a compound of a formula (3), including reacting a compound of a formula (1) with a compound of a formula (2) by using a tertiary alcohol and a base:

##STR00001##

where R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8, and R.sup.9 are each independently a hydrogen atom, a halogen atom, a (C1-C4)alkyl, or a (C1-C4)alkoxy, the amount of the base used is 2.0-4.0 equivalents per 1 equivalent of the compound of formula (2), the amount of the tertiary alcohol used is 0.3-2.5 equivalents per 1 equivalent of the compound of formula (2), the base is a plurality of compounds comprising a lithium-containing base as a first compound, and a second compound selected from the group consisting of alkali metal hydrides, alkali metal amides, alkoxides, alkyl metals, alkali metals, and organic bases, and the reaction is performed in the presence of an aromatic hydrocarbon solvent.

A method for producing a compound of a formula (3), including reacting a compound of a formula (1) with a compound of a formula (2) by using a tertiary alcohol and a base:

##STR00001##

where R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8, and R.sup.9 are each independently a hydrogen atom, a halogen atom, a (C1-C4)alkyl, or a (C1-C4)alkoxy, the amount of the base used is 2.0-4.0 equivalents per 1 equivalent of the compound of formula (2), the amount of the tertiary alcohol used is 0.3-2.5 equivalents per 1 equivalent of the compound of formula (2), the base is a plurality of compounds comprising a lithium-containing base as a first compound, and a second compound selected from the group consisting of alkali metal hydrides, alkali metal amides, alkoxides, alkyl metals, alkali metals, and organic bases, and the reaction is performed in the presence of an aromatic hydrocarbon solvent.

A method for producing a compound of a formula (3), including reacting a compound of a formula (1) with a compound of a formula (2) by using a tertiary alcohol and a base:

##STR00001##

where R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8, and R.sup.9 are each independently a hydrogen atom, a halogen atom, a (C1-C4)alkyl, or a (C1-C4)alkoxy, the amount of the base used is 2.0-4.0 equivalents per 1 equivalent of the compound of formula (2), the amount of the tertiary alcohol used is 0.3-2.5 equivalents per 1 equivalent of the compound of formula (2), the base is a plurality of compounds comprising a lithium-containing base as a first compound, and a second compound selected from the group consisting of alkali metal hydrides, alkali metal amides, alkoxides, alkyl metals, alkali metals, and organic bases, and the reaction is performed in the presence of an aromatic hydrocarbon solvent.

There is disclosed a cyclic process for producing taurine from monoethanolamine comprising the steps of: (a) recovering monoethanolamine sulfate from an aqueous mother liquor solution; (b) reacting the monoethanolamine sulfate with sulfuric acid to form an aqueous solution comprised of monoethanolamine bisulfate; (c) heating the aqueous solution comprised of the monoethanolamine sulfate and optionally added monoethanolamine sulfate to yield 2-aminoethyl hydrogen sulfate ester; and (d) reacting the ester with ammonium sulfite or an alkali sulfite to yield taurine.

There is disclosed a cyclic process for producing taurine from monoethanolamine comprising the steps of: (a) recovering monoethanolamine sulfate from an aqueous mother liquor solution; (b) reacting the monoethanolamine sulfate with sulfuric acid to form an aqueous solution comprised of monoethanolamine bisulfate; (c) heating the aqueous solution comprised of the monoethanolamine sulfate and optionally added monoethanolamine sulfate to yield 2-aminoethyl hydrogen sulfate ester; and (d) reacting the ester with ammonium sulfite or an alkali sulfite to yield taurine.