本實驗利用HF(Hartree-Fock)/6-31G及天然鍵解軌域(Natural Bond Orbital)計算方法，來研究薑黃素(curcumin, CCM)及去甲氧基薑黃素(didemethylated curcumin, DCCM)對SeO32-鍵結機制，透過靜電位能圖(electronic potential plots，EPP圖)可得知CCM及DCCM的正負電荷場的分布，這可提供一個很重要的訊息是:當外界有陰陽離子要和CCM及DCCM產生鍵結時，陽離子會靠近keto-enol負電場位置，然而，當陰離子靠近時，則是會傾向氫原子所帶的正電場，而本實驗的主角SeO32-則是屬於陰離子，當它靠近CCM及DCCM時，會跑向正電場的位置，為了更進一步了解它們所生成的機制，首先先將CCM異構物做結構最佳化計算，接著求出CCM/SeO32-錯合物不同異構物的穩定能，並找出最穩定的結構，之後將錯合物中的CCM氫原子分成兩大部分來探討:長碳鏈與苯環上的氫原子以及甲氧基上的氫原子，去分析這些氫原子的原子電荷值變化量，發現SeO32-一旦靠近CCM時，長碳鏈與苯環上的氫原子及甲氧基部分氫原子的電荷值有增加的現象，因此可以推斷有氫鍵的生成，之後更進一步去分析這些氫原子與SeO32-氧原子的距離以及C-H鍵長的變化，分析結果可以確認長碳鏈與苯環上的氫原子及甲氧基部分氫原子與SeO32-氧原子之間有氫鍵的生成，一旦有氫鍵生成後，甲氧基的C-H鍵長會縮短，然而，長碳鏈與苯環的C-H鍵長會增加，接著利用NBO方法去分析E(2)及Δs%值，可以發現長碳鏈及苯環所獲得的E(2)及Δs%值都比甲氧基來的高，由此可知長碳鏈及苯環所受的氫鍵作用力比甲氧基來的強，而且其E(2)值高，主要受到超共軛效應影響，所以C-H鍵長會增加，然而，甲氧基的E(2)值不高，超共軛效應微弱，主要是由重新混成主導，導致C-H鍵長有縮短的現象，而在此所受到的微弱作用力則為非典型氫鍵。
另外，從DCCM結果來看，DCCM左右兩端各有兩個羥基(OH)，其中兩個羥基的氫原子有分子內氫鍵的生成，另兩個羥基則無，而此未遭受分子內氫鍵的氫原子是屬於酸質子，其酸性強度比CCM來的高，可視為路易士酸，這有利於和路易士鹼SeO32-作用，從理論計算結果可得知SeO32-會抓取DCCM兩端酚基位置上的氫原子。
從CCM及DCCM抓取SeO32-的能力來看，CCM是利用螯合的方式抓取SeO32-，一個CCM只能抓取一個SeO32-，然而，DCCM兩側都可抓取SeO32-，由此結果可以得知DCCM抓取SeO32-的能力比CCM來的強。

The electron potential plots are informative. Firstly, the most acidic enolic proton of curcumin is buried in the negatively charged electric field resulting from lone-paired electrons on the two oxygen atoms. Curcumin (CCM) can thus chelate the attracted metal cations through its conjugate base, CCM anion, and lead to the coexistence of free CCM and metal-binded CCM. This conclusion is consistent with the reported NMR data. Furthermore, this prevents the acid-base interaction between selenite and enolic hydrogen of CCM. This is also true for the phenolic hydrogen. On the other hand, the positively charged hydrogen atoms, including sp2-tpye hydrogen atoms and methyl hydrogen atoms, can form H-bonding with the attracted selenite oxygen atom(s). The phenolic hydrogen at both ends of CCM is protected by intramolecular H-bonding and, therefore, allow the methyl hydrogen atom to form improper (or un-conventional) H-bonding with selenite. In the closely contacted solid state, this phenolic hydrogen is forced to form H-bonding with the oxygen atom of selenite. This explains the intensity enhancement of the O-H stretching peak in IR spectra.

In the didemethyl CCM (DCCM), one of the two adjacent hydroxyl groups (in each end of DCCM molecule) reveal acidic nature. This enables the acid-base interaction of DCCM and selenite to generate more stabilized adduct as compared to CCM. Unlike CCM, furthermore, one DCCM molecule can bind two selenites through each end of phenolic fragment. This explains that DCCM exhibited (1) better activity than CCM observed in preventing selenite induced lens crystallin aggregation and (2) larger binding affinity than CCM observed by ITC experiments. The values of soichiometry, 1.22 for CCM and 1.90 for DCCM are also understood through the senelie-binding mechanisms: acid-base interaction for DCCM and H-bonding for CCM.

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