Synthesis and biological activity of disubstituted triazinyl carbamyl urea 芳甲酰基脲的合成及其生物活性
2.
Hydantoinase ( ec 3 . 5 . 2 ) hydrolyzes its substrate 5 ' - monosubstantial hydantoin to enantiomerical n - carbamyl - amino acids and in turn , the resulting product can be chemically or enzymatically converted into the corresponding optically active amino acids 海因酶( hydantoinase ， ec3 . 5 . 2 ) ，是一类催化海因、 5 ’ -单替代海因及其衍生物环酰胺键断裂的酰胺水解酶。
3.
Abstract : study on the synthesis of n - methyl carbamyl chloride underdifferent ratio of input materials and the yield of the termination products methyl isocyanate . the yield is raised from 81 . 89 % to 86 . 23 % 文摘:研究了在其它工艺条件不变的情况下，改变光气与甲胺的配比对合成n -甲氨基甲酰氯的影响。光气甲胺（摩尔比）由1 35 1降至1 25 1 ，最终产物甲基异氰酸酯收率由81 89升高至86 23 。
4.
As far as the enzymatic activity is concerned , on the one hand , strain yz - ii6 has higher d - hydantoinase activity and lower d - carbamoylase activity so as not to be suitable for one - step bioconversion of d - amino acids , on the other hand , the higher hydantoinase activity , engineered strain in particular , may be convenient to be as a biocatalyst to produce n - carbamyl d - amino acids which hard to find in the markets Yz - 6菌具有较高的海因酶活性，但n -氨甲酰基d -氨基酸酰氨水解酶活性很低，仍不适合用于d -型氨基酸生产工艺中的一步法转化。另一方面，含海因酶基因的人工菌株不但酶活性高，也排除了天然菌株转化生产d -型氨基酸过程中的一些副产物。
5.
In bioconversion of a d - amino acid and its derivative , the substrate , 5 ' - monosubstituted hydantoin is firstly transferred into an intermediate , d - carbamyl amino acid by d - hydantoinase , and in turn into an optically active d - amino acid by either d - carbamoylase or chemical , nano2 . nowadays , the bioconversion of d - amino acids has been industrialized by enzymes , so called one - step process D -型氨基酸及其衍生物的生物转化，经历两个反应历程，首先是在海因酶的作用下，催化5 -单替代海因形成氨甲酰类氨基酸中间物，后者再在酶或化学的作用下，生成相应的光学活性氨基酸或其衍生物。
