刚性连接子通过引入环（脂肪环、脂肪杂环、芳香环等）来替代线性连接子，可以有效减少药物分子中可旋转键数量，限制化合物构象，从而有利于提高药物分子对靶点的结合稳定性；另一方面，刚性环相比线性分子更容易调节药物分子的物理化学性质，改善其DMPK，目前在蛋白降解剂类药物中得到广泛应用。
Cyclohexane-1,4-diyldimethanamine
tert-Butyl 3-(3-hydroxypropyl)azetidine-1-carboxylate
trans-Ethyl 4-(aminomethyl)cyclohexanecarboxylate hydrochloride
cis-1-(tert-Butoxycarbonyl)-3-fluoropiperidine-4-carboxylic acid
trans-1-(tert-Butoxycarbonyl)-3-fluoropiperidine-4-carboxylic acid
1-(tert-Butoxycarbonyl)-3,3-difluoropiperidine-4-carboxylic acid
4-Bromophenylacetonitrile
3-(Piperazin-1-yl)propanoic acid
tert-Butyl (2-(azetidin-3-yl)ethyl)carbamate hydrochloride
4-(Methoxycarbonyl)cubane-1-carboxylic acid
1'-(tert-Butoxycarbonyl)-[1,4'-bipiperidine]-4-carboxylic acid
1,4-Bis(2-bromoethoxy)benzene
4-Ethynylbenzoic acid
tert-Butyl 4-(2-chloroethyl)piperazine-1-carboxylate
Ethyl 2-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)acetate
1,4-Bis(2-chloroethyl)piperazine
1-N-Boc-4-(4-Bromophenyl)piperidine
2-(4-(2-Methoxy-2-oxoethyl)phenyl)acetic acid
tert-Butyl N-(4-(2-(((tert-butoxy)carbonyl)amino)ethyl)phenyl)carbamate
2-(trans-4-Aminocyclohexyl)acetonitrile
tert-Butyl 7-(aminomethyl)-2-azaspiro[3.5]nonane-2-carboxylate
tert-Butyl (trans-4-(cyanomethyl)cyclohexyl)carbamate
Benzyl 3-(hydroxymethyl)azetidine-1-carboxylate
2-(4-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)piperidin-1-yl)acetic acid
tert-Butyl 7-(hydroxymethyl)-2-azaspiro[3.5]nonane-2-carboxylate
Benzyl 4-(2-hydroxyethyl)piperidine-1-carboxylate
Methyl 2-(4-(hydroxymethyl)phenyl)acetate
Methyl 2-(4-formylphenyl)acetate
