Using the both quantum chemical and molecular dynamics calculations free energy profiles during membrane permeable processes of Ala-containing cyclic dipeptides were evaluated with moderate computational costs. Since the balance between hydrophobicity and hydrophilicity is a key factor in the membrane permeation processes, Ala-Ala and Ala-Pro might be permeable, but Ala-Asn is not owing to the high free energy barrier at the membrane center. This protocol is useful to roughly distinguish whether a given compound has high permeability or not.

中文翻译：

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通过量子化学和分子动力学计算近似估计环状二肽的溶解度和膜渗透性

使用量子化学和分子动力学计算，在中等计算成本下评估含 Ala 环二肽的膜渗透过程中的自由能分布。由于疏水性和亲水性之间的平衡是膜渗透过程中的关键因素，因此 Ala-Ala 和 Ala-Pro 可能具有渗透性，但 Ala-Asn 并非由于膜中心的高自由能势垒。该协议可用于粗略区分给定的化合物是否具有高渗透性。