Hartley J A, Mattes W B, Vaughan K, Gibson N W
Laboratory of Molecular Pharmacology, National Cancer Institute, Bethesda, MD 20892.
Carcinogenesis. 1988 Apr;9(4):669-74. doi: 10.1093/carcin/9.4.669.
The base sequence selectivity for reaction at the guanine-N7 position was examined for a series of structurally related triazenes by a modification of a standard DNA sequencing method. The monomethyl and monochloroethyl triazenes alkylate guanines extensively at the N7 position with a general preference for runs of contiguous guanines, similar to, but not as striking as that observed previously for the chloroethylnitrosoureas. In contrast to the nitrosoureas, the triazenes had patterns of base sequence selectivity that differed somewhat from agent to agent, with the monochloro-ethylphenyltriazene having the pattern most different from the others in the series. Thus, the nature of the nonalkylating portion of the molecule can influence the ultimate alkylation preference. The monoethylating analogues alkylated weakly with little sequence preference, and the dimethyl analogues were essentially unreactive in this system.
通过对标准DNA测序方法进行改进，研究了一系列结构相关的三氮烯在鸟嘌呤-N7位置反应的碱基序列选择性。单甲基和单氯乙基三氮烯在N7位置广泛烷基化鸟嘌呤，通常优先选择连续的鸟嘌呤序列，这与之前观察到的氯乙基亚硝基脲类似，但不如其显著。与亚硝基脲不同，三氮烯的碱基序列选择性模式因试剂而异，单氯乙基苯基三氮烯的模式与该系列中的其他试剂最不同。因此，分子中非烷基化部分的性质会影响最终的烷基化偏好。单乙基化类似物烷基化较弱，几乎没有序列偏好，而二甲基类似物在该系统中基本无反应。
