Voyushina T L, Potetinova J V, Milgotina E I, Stepanov V M
V.M. Stepanov's Laboratory of Protein Chemistry, Institute of Genetics and Selection of Industrial Microorganisms, Moscow, Russia.
Bioorg Med Chem. 1999 Dec;7(12):2953-9. doi: 10.1016/s0968-0896(99)00237-0.
Two ways for semi-enzymatic preparation of the peptide aldehydes are proposed: (1) enzymatic acylation of amino alcohols with acyl peptide esters and subsequent chemical oxidation of the resulting peptide alcohols with DMSO/acetic anhydride mixture or (2) enzymatic acylation of the preliminarily obtained by a chemical route amino aldehyde semicarbazones. Subtilisin 72, serine proteinase with a broad specificity, distributed over macroporous silica, was used as a catalyst in both cases. Due to the practical absence of water in the reaction mixtures the yields of the products in both enzymatic reactions were nearly quantitative. The second way seems to be more attractive because all chemical stages were carried out with amino acid derivatives, far less valuable compounds than peptide ones. A series of peptide aldehydes of general formula Z-Ala-Ala-Xaa-al (where Xaa-al = leucinal, phenylalaninal, alaninal, valinal) was obtained. The inhibition parameters for these compounds, in the hydrolysis reactions of corresponding chromogenic substrates for subtilisin and alpha-chymotrypsin, were determined.
（1）用酰基肽酯对氨基醇进行酶促酰化，然后用二甲基亚砜/乙酸酐混合物对所得的肽醇进行化学氧化；或（2）对通过化学途径预先获得的氨基醛缩氨基脲进行酶促酰化。在这两种情况下，均使用固定在大孔硅胶上的具有广泛特异性的丝氨酸蛋白酶枯草杆菌蛋白酶72作为催化剂。由于反应混合物中实际无水，两种酶促反应的产物收率几乎都是定量的。第二种方法似乎更具吸引力，因为所有化学步骤都是用氨基酸衍生物进行的，这些化合物比肽类化合物的价值低得多。获得了一系列通式为Z-Ala-Ala-Xaa-al（其中Xaa-al =亮氨醛、苯丙氨醛、丙氨醛、缬氨醛）的肽醛。测定了这些化合物在枯草杆菌蛋白酶和α-胰凝乳蛋白酶相应显色底物水解反应中的抑制参数。
