The present invention relates to processes for the formation of pyridinedicarboxylic acid (PDCA), in particular, 2,4-pyridinedicarboxylic acid (2,4-PDCA) and 2,5-pyridinedicarboxylic acid (2,5-PDCA), and mono- and diester derivatives thereof, from 3,4-dihydroxybenzoic acid, via a biocatalytic reaction using, for example, a protocatechuate dioxygenase such as protocatechuate 4,5-dioxygenase or protocatechuate 2,3-dioxygenase, and a nitrogen source. The invention also relates to copolymers that comprise the pyridinedicarboxylic acid monomers and derivatives thereof, processes for the formation of the copolymers and uses for the copolymers.

The present invention relates to processes for the formation of pyridinedicarboxylic acid (PDCA), in particular, 2,4-pyridinedicarboxylic acid (2,4-PDCA) and 2,5-pyridinedicarboxylic acid (2,5-PDCA), and mono- and diester derivatives thereof, from 3,4-dihydroxybenzoic acid, via a biocatalytic reaction using, for example, a protocatechuate dioxygenase such as protocatechuate 4,5-dioxygenase or protocatechuate 2,3-dioxygenase, and a nitrogen source. The invention also relates to copolymers that comprise the pyridinedicarboxylic acid monomers and derivatives thereof, processes for the formation of the copolymers and uses for the copolymers.

The present disclosure relates to improved processes for preparing 4-amino-6-(heterocyclic)picolinates.

The present disclosure relates to improved processes for preparing 4-amino-6-(heterocyclic)picolinates.

The present invention generally relates to an improved process for the preparation of Trigonelline or pharmaceutically acceptable salts thereof and to processes for its purification.

The present invention generally relates to an improved process for the preparation of Trigonelline or pharmaceutically acceptable salts thereof and to processes for its purification.

A process for the preparation of compound of formula I is provided: Formula (I) where R.sub.1 and R.sub.2 are as defined in the description.

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A process for the preparation of compound of formula I is provided: Formula (I) where R.sub.1 and R.sub.2 are as defined in the description.

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Methods for preparing 5-fluoro-6-(bromo or chloro)picloram analogs, or derivatives thereof, from picloram acid, picloram ester, or the nitrile analog of picloram are provided. The methods include chemical process steps that: (1) introduce a phthaloyl group onto the 4-amino substituent of picloram acid, picloram ester, or the nitrile analog of picloram, (2) add 2 fluorine atoms at the 5,6-positions of the pyridine ring using halex fluorination chemistry, (3) remove the phthaloyl group, hydrolyze the ester or nitrile substituent, and add chlorine or bromine to the 6-position by treatment with an acid and water, and finally, (4) esterify the 5-fluoro-6-(bromo or chloro)picloram acid produced in step (3) to a 5-fluoro-6-(bromo or chloro)picloram ester.

Methods for preparing 5-fluoro-6-(bromo or chloro)picloram analogs, or derivatives thereof, from picloram acid, picloram ester, or the nitrile analog of picloram are provided. The methods include chemical process steps that: (1) introduce a phthaloyl group onto the 4-amino substituent of picloram acid, picloram ester, or the nitrile analog of picloram, (2) add 2 fluorine atoms at the 5,6-positions of the pyridine ring using halex fluorination chemistry, (3) remove the phthaloyl group, hydrolyze the ester or nitrile substituent, and add chlorine or bromine to the 6-position by treatment with an acid and water, and finally, (4) esterify the 5-fluoro-6-(bromo or chloro)picloram acid produced in step (3) to a 5-fluoro-6-(bromo or chloro)picloram ester.