The present invention relates to a method of production of 4-boronophenylalanine (BPA) from 4-iodophenylalanine, in which all the functional groups of the amino acid are protected by benzyl protection method, and which uses isopropyl magnesium halogenide stabilized by a complexation base, and subsequent condensation of the resulting Grignard reagent with a boric acid ester. The final reaction step, catalytic hydrogenolysis or transfer hydrogenolysis of protecting groups on the amino acid, occurs after hydrolysis of the boronate ester groups.

Processes for synthesizing new compounds that may usefully be employed in organic synthesis, especially in the synthesis of vitamin A or -carotene and derivatives thereof, e.g. canthaxanthin, astaxanthin or zeaxanthin are disclosed. The new compounds are especially useful as intermediates (building blocks) in the synthesis of vitamin A or -carotene, preferably vitamin A.

Processes for synthesizing new compounds that may usefully be employed in organic synthesis, especially in the synthesis of vitamin A or -carotene and derivatives thereof, e.g. canthaxanthin, astaxanthin or zeaxanthin are disclosed. The new compounds are especially useful as intermediates (building blocks) in the synthesis of vitamin A or -carotene, preferably vitamin A.

The present disclosure relates to novel, scalable methods of making substituted tricyclic compounds that are useful to treat and/or prevent HBV and/or HBV-HDV infection and related conditions in a subject.

The present application relates to a process for the preparation of crystalline form A of palbociclib having specific surface area more than 2 m.sup.2/g comprising one-pot process for the preparation of compound of formula (IV). The present application further relates to the preparation of acid-addition salts of palbociclib and their use for the synthesis of crystalline form A of palbociclib having specific surface area more than 2 m.sup.2/g.

The present application relates to a process for the preparation of crystalline form A of palbociclib having specific surface area more than 2 m.sup.2/g comprising one-pot process for the preparation of compound of formula (IV). The present application further relates to the preparation of acid-addition salts of palbociclib and their use for the synthesis of crystalline form A of palbociclib having specific surface area more than 2 m.sup.2/g.

The present invention relates to a method of production of 4-boronophenylalanine (BPA) from 4-iodophenylalanine, in which all the functional groups of the amino acid are protected by benzyl protection method, and which uses isopropyl magnesium halogenide stabilized by a complexation base, and subsequent condensation of the resulting Grignard reagent with a boric acid ester. The final reaction step, catalytic hydrogenolysis or transfer hydrogenolysis of protecting groups on the amino acid, occurs after hydrolysis of the boronate ester groups.

The present application relates to a process for the preparation of crystalline form A of palbociclib having specific surface area more than 2 m.sup.2/g comprising one-pot process for the preparation of compound of formula (IV). The present application further relates to the preparation of acid-addition salts of palbociclib and their use for the synthesis of crystalline form A of palbociclib having specific surface area more than 2 m.sup.2/g.

The present application relates to a process for the preparation of crystalline form A of palbociclib having specific surface area more than 2 m.sup.2/g comprising one-pot process for the preparation of compound of formula (IV). The present application further relates to the preparation of acid-addition salts of palbociclib and their use for the synthesis of crystalline form A of palbociclib having specific surface area more than 2 m.sup.2/g.

The present invention relates to the compound of formula (I). The invention further relates to the compound of formula (II). The invention further relates to the synthesis of these compounds as well as to their use in organic synthesis, especially in the synthesis of vitamin A or p-carotene and derivatives thereof, e.g. canthaxanthin, astaxanthin or zeaxanthin.

##STR00001##