The high-valent manganese-oxo species of Mn-TMPyP4 porphyrin interacts in the minor grooves of AT-rich regions of DNA and mediates hydroxylation of C–H bonds of deoxyribose leading to DNA break. The reaction was observed at different pHs. It is shown that the hydroxylation was not efficient at low pH (pH 6) while it worked well at higher pH (pH 8). Deprotonation of the coordinated water molecule, trans to the manganese-oxo entity, into a hydroxide anion drives high-valent manganese-oxo porphyrin toward hydroxylation at pH > 7.

中文翻译：

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在p ķ_一个近端水分子的值反式到高价锰^V ø卟啉：向反应性通过pH控制

Mn-TMPyP4卟啉的高价锰-氧物种在富含AT的DNA区域的小沟中相互作用，并介导脱氧核糖C–H键的羟基化，从而导致DNA断裂。在不同的pH下观察到该反应。结果表明，羟基化在低pH（pH 6）时无效，而在较高pH（pH 8）时效果很好。配位的水分子反质子化，转变成锰-氧代实体，变成氢氧根阴离子，驱使高价锰-氧代卟啉在pH> 7时发生羟基化。