环醇假说（cyclol hypothesis），为第一个折叠的球状蛋白质结构模型概念 ，这是多萝西·林奇在20世纪30年代基于三个假设提出的。首先，该假设假设两个肽键由Cyclol反应交联而成（图1），这些交联键是共价的肽的同系物之间的氢键，而非“共价键”。这些反应已被发现存在于麦角肽和其他化合物中。第二，该假设提出在某些条件下，氨基酸会自然地在最大数量上进行Cyclol交联反应，生成Cyclol分子（图2）和Cyclol结构（图3）。这些Cyclol分子和Cyclol结构从来没有被观察到。最后，该假设认为球状蛋白质的三级结构对应的正多面体和半规则的多面体形成的Cyclol结构是没有自由边缘的。这种“封闭式的Cyclol”分子也没有被观察到。

The cyclol hypothesis is the first structural model of a folded, globular protein. It was developed by Dorothy Wrinch in the late 1930s, and was based on three assumptions. Firstly, the hypothesis assumes that two peptide groups can be crosslinked by a cyclol reaction (Figure 1); these crosslinks are covalent analogs of non-covalent hydrogen bonds between peptide groups. These reactions have been observed in the ergopeptides and other compounds. Secondly, it assumes that, under some conditions, amino acids will naturally make the maximum possible number of cyclol crosslinks, resulting in cyclol molecules (Figure 2) and cyclol fabrics (Figure 3). These cyclol molecules and fabrics have never been observed. Finally, the hypothesis assumes that globular proteins have a tertiary structure corresponding to Platonic solids and semiregular polyhedra formed of cyclol fabrics with no free edges. Such "closed cyclol" molecules have not been observed either.