Protein phosphorylation plays a very important role in biochemical processes. Enzymes in which phosphate groups are introduced are called kinases, and enzymes in which phosphate groups are removed are called phosphatases. Protein phosphorylation can occur on many kinds of amino acids (the main unit of protein), among which serine, threonine, and tyrosine are the main ones.

Boc-acid anhydride is often used as a tert-butoxycarbonyl protecting group in organic synthesis, especially for the protection of amino groups in amino acids [1]. Widely used in the synthesis of various products such as medicine, protein and peptide synthesis, biochemistry, food, cosmetics, etc. This article will briefly introduce the method and mechanism of Boc-anhydride introducing and removing Boc protecting group.

Acylation is one of the most common organic chemical reactions, and the commonly used catalysts for acylation reactions are pyridine and triethylamine. In 1967, Litvinenko et al. found that 4-dimethylaminopyridine (DMAP) was used to catalyze the benzoylation reaction of m-chloroaniline, and the reaction rate increased by about 104-105 times compared with pyridine as a catalyst. Therefore, 4-dimethylaminopyridine, as a new type of high-efficiency acylation catalyst, has attracted more and more people's favor.

Dibromotriphenylphosphine was first used in the synthesis reaction in 1959 to prepare bromide and acid bromide from alcohol and carboxylic acid, and it was also used in the dehydration reaction of amides and oximes to nitriles. Now it has been used as a general reagent in many reactions

In the previous article, we reviewed the common alkoxycarbonyl amino protecting groups. In this article, we will review another common amino protecting group—the alkyl protecting group. These common protecting groups mainly include: trityl (Trt), benzyl (Bn), p-methoxybenzyl (PMB), 2,4-dimethoxybenzyl (DMB).