The Instruction of Eribulin mesylate intermediate

Eribulin mesylate is a synthetic drug that is used to treat breast cancer, non-small cell lung cancer, and other types of cancer.
It is a type of medication called a microtubule inhibitor, which works by interfering with the growth and division of cancer cells.
Eribulin mesylate is usually given intravenously, and the drug is produced through a series of chemical reactions that involve several intermediate steps.

One of the key intermediates in the production of eribulin mesylate is 2-[(2S)-2-[[2-(4-chlorophenyl)-5,6-dihydroimidazo[1,2-d][1,4]benzoxazepin-9-yl]amino]-N-(4-hydroxyphenyl)acetamide.
This intermediate is synthesized through a series of steps that involve the formation of an imidazole ring, the introduction of a benzoxazepine ring, and the coupling of the two rings through a condensation reaction.

The first step in the synthesis of 2-[(2S)-2-[[2-(4-chlorophenyl)-5,6-dihydroimidazo[1,2-d][1,4]benzoxazepin-9-yl]amino]-N-(4-hydroxyphenyl)acetamide is the production of an imidazole ring.
This is achieved through a reaction known as N- alkylation, which involves the treatment of a substituted imidazole with a compound called a halogenating agent.
The halogenating agent used in this case is 4- chlorophenyl borate, which reacts with the imidazole to form a new carbon-carbon bond and introduce the chlorine atom into the molecule.

The next step in the synthesis of 2-[(2S)-2-[[2-(4-chlorophenyl)-5,6-dihydroimidazo[1,2-d][1,4]benzoxazepin-9-yl]amino]-N-(4-hydroxyphenyl)acetamide is the introduction of a benzoxazepine ring.
This is achieved through a reaction known as a Suzuki reaction, which involves the treatment of a boronic acid with a palladium catalyst and a phosphine ligand.
The boronic acid used in this case is 2-[(2S)-2-[(4-hydroxyphenyl)amino]-5,6-dihydroimidazo[1,2-d][1,4]benzoxazepin-9-yl]acetic acid, which is treated with palladium acetate and a phosphine ligand to form the benzoxazepine ring.

The final step in the synthesis of 2-[(2S)-2-[[2-(4-chlorophenyl)-5,6-dihydroimidazo[1,2-d][1,4]benzoxazepin-9-yl]amino]-N-(4-hydroxyphenyl)acetamide is the coupling of the two rings through a condensation reaction.
This is achieved through a reaction known as a peptide coupling reaction, which involves the treatment of an amino acid with a substituted amide.
The amino acid used in this case is L-phenylalanine, and the substituted amide is 2-[(2S)-2-[[2-(4-chlorophenyl)-5,6-dihydroimidazo[1,2-d][1,4]benzoxazepin-9-yl]amino]-N-(4-hydroxyphenyl)acetamide.
This reaction results in the formation of a new carbon-carbon bond and the completion of the synthesis of 2-[(2S)-2-[[2-(4-chlorophenyl)-5,6-dihydroimidazo[1,2-d][1,4]benzoxazepin-9-yl]amino]-N-(4-hydroxyphenyl)acetamide.