Willett Cammy D, Lerch Robert N, Goyne Keith W, Leigh Nathan D, Lin Chung-Ho, Roberts Craig A
Nat Prod Commun. 2014 Sep;9(9):1283-6.
Naturally occurring benzoxazinones (Bx) are a highly reactive class of compounds that have received particular attention in the past several decades. Recently, we identified 2-β-D-glucopyranosyloxy-4-hydroxy-1,4-benzoxazin-3-one (DIBOA-Glc) as the compound present in the roots of Eastern gamagrass {Tripsacum dactyloides (L.)} responsible for atrazine degradation. However, characterization of the DIBOA-Glc/atrazine degradation reaction has been limited due to difficulties in attaining sufficient quantities of purified DIBOA-Glc. The objective of the study was to develop a simple purification and isolation method for obtaining bulk quantities of highly purified DIBOA-Glc. T. dactyloides roots were extracted with 90% aqueous methanol, and the crude extract was fractionated using an HPLC equipped with a C8 semi-prep column and fraction collector. UHPLC-DAD-MS/MS was used to confirm the identity of DIBOA-Glc in the fractions collected. Analysis by 13C and 1H NMR and DAD indicated that 542 mg of DIBOA-Glc with a purity of > 99% was obtained. The reactivity of the DIBOA-Glc was confirmed in a 16 hour assay with atrazine, which resulted in 48.5% ± 1.2% (SD) atrazine degradation. The method described here offers several advantages over existing extraction and synthesis methods, which are more cumbersome, use hazardous chemicals, and yield only small quantities of purified compound. The newly developed method will facilitate future research characterizing the chemical behavior of DIBOA-Glc and determine its potential as an atrazine mitigation and remediation tool.
天然存在的苯并恶嗪酮（Bx）是一类高反应性化合物，在过去几十年中受到了特别关注。最近，我们鉴定出2-β-D-吡喃葡萄糖氧基-4-羟基-1,4-苯并恶嗪-3-酮（DIBOA-Glc）是东部稷（Tripsacum dactyloides (L.)）根中存在的负责降解莠去津的化合物。然而，由于难以获得足够量的纯化DIBOA-Glc，DIBOA-Glc/莠去津降解反应的表征受到限制。本研究的目的是开发一种简单的纯化和分离方法，以获得大量高纯度的DIBOA-Glc。用90%的甲醇水溶液提取东部稷的根，粗提物使用配备C8半制备柱和馏分收集器的高效液相色谱进行分馏。超高效液相色谱-二极管阵列-串联质谱用于确认收集馏分中DIBOA-Glc的身份。通过13C和1H核磁共振以及二极管阵列分析表明，获得了542 mg纯度>99%的DIBOA-Glc。在与莠去津进行的16小时测定中证实了DIBOA-Glc的反应性，结果莠去津降解率为48.5%±1.2%（标准差）。本文所述方法与现有的提取和合成方法相比具有几个优点，现有方法更繁琐，使用危险化学品，且只能得到少量纯化化合物。新开发的方法将有助于未来研究表征DIBOA-Glc的化学行为，并确定其作为莠去津缓解和修复工具的潜力。
