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。
2-(4-Chlorophenyl)ethanol
tert-Butyl 4-(2-oxoethyl)piperidine-1-carboxylate
tert-Butyl (3-formylbicyclo[1.1.1]pentan-1-yl)carbamate
2-(3-((tert-Butoxycarbonyl)amino)cyclobutyl)acetic acid
tert-Butyl 4-(hydroxymethyl)benzylcarbamate
1,4-Cyclohexanedimethanol
Methyl 1-(5-bromopyrimidin-2-yl)piperidine-4-carboxylate
tert-Butyl 4-(4-aminophenyl)piperazine-1-carboxylate hydrochloride
(4-(3-Bromopropoxy)phenyl)boronic acid
2-(4-(3-Bromopropoxy)phenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane
tert-Butyl 3-(2-hydroxyethyl)azetidine-1-carboxylate
tert-Butyl 2,7-diazaspiro[3.5]nonane-7-carboxylate hydrochloride
Ethyl 3-(4-bromophenyl)propanoate
2-(4-Boronophenyl)acetic acid
tert-Butyl 2,6-diazaspiro[3.3]heptane-2-carboxylate
tert-Butyl 6-hydroxy-2-azaspiro[3.3]heptane-2-carboxylate
tert-Butyl 4-(azetidin-3-yl)piperazine-1-carboxylate
tert-Butyl 4-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzoyl)piperazine-1-carboxylate
Methyl 4-(aminomethyl)bicyclo[2.2.2]octane-1-carboxylate
tert-Butyl (trans-4-(2-hydroxyethyl)cyclohexyl)carbamate
Ethyl 2-(trans-4-((tert-butoxycarbonyl)amino)cyclohexyl)acetate
4-Ethynylphenylacetonitrile
2-(4-(((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)methyl)phenyl)acetic acid
2-(cis-4-((tert-Butoxycarbonyl)amino)cyclohexyl)acetic acid
4-(2-((tert-Butoxycarbonyl)amino)ethyl)benzoic acid
tert-Butyl 2-cyano-7-azaspiro[3.5]nonane-7-carboxylate
tert-Butyl 4-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)piperidine-1-carboxylate
2-(4-Aminocyclohexyl)ethanol
2-(4-(4-Aminophenyl)piperazin-1-yl)ethanol
Methyl 4-(2-hydroxyethyl)benzoate
