苯并呋喃酮衍生物结构对其DPPH捕获能力的影响

采用自由基比色法考察苯并呋喃酮衍生物结构对其DPPH捕获能力的影响。结果发现，母体苯环5，7位上甲基和叔丁基的改变以及取代苯环上强供电子取代基的存在对苯并呋喃酮衍生物的DPPH捕获能力没有明显影响。取代苯环2’位存在明显的位阻作用，对苯并呋喃酮衍生物的DPPH捕获能力具有明显的抑制作用：并且当此位为不含活泼氢的氢键受体取代基时，苯并呋喃酮衍生物的DPPH捕获能力会由于取代基与3位活泼氢的氢键作用而被进一步削弱；但此位为含有活泼氢的氢键受体取代基时，此取代基的氢将会由于3位活泼氢与取代基的氢键作用而活化，从而使其位阻作用得到一定程度的抑制。

Structure Effect of Benzofuranone Derivative on the Scavenging Ability to DPPH

The structure effect of benzofuranone derivatives on the scavenging ability to DPPH was studied using radical colorimetry in this paper. The results showed that: the change of methyl and tert-butyl group in 5 and 7 position of mother benzene ring of benzofuranone and the presentation of strong electron-donating substitute in substituted benzene ring have little influences on the scavenging ability of benzofuranone derivatives to DPPH. Substitute of 2’-position will prevent the attack of benzofuranone toward radicals, which weak the scavenging ability of benzofuranone derivatives to DPPH. And the scavenging ability to DPPH will be weakened further, when the substitute of 2’-position is without reactive hydrogen and can form hydrogen bond with 3- reactive hydrogen. But when the substitute of 2’-position is with reactive hydrogen, the reactive hydrogen will be actived due to the formation of hydrogen bond between substitute group with 3- reactive hydrogen, and the position hindrance will be made up in a great extent.