(4-cyanobenzyl)-L-proline

(4-ethynylbenzyl)-L-proline

((4-methylthiazol-5-yl)methyl)-L-proline

((5-(hydroxymethyl)furan-2-yl)methyl)-L-proline

((3,5-dimethylisoxazol-4-yl)methyl)-L-proline

((3-fluoropyridin-2-yl)methyl)-L-proline

(3-hydroxybenzyl)-L-proline

(4-methylbenzyl)-L-proline

(thiophen-2-ylmethyl)-L-proline

((1-methyl-1H-pyrrol-2-yl)methyl)-L-proline

(pyridin-2-ylmethyl)-L-proline

benzyl-L-proline

((tetrahydrofuran-3-yl)methyl)-L-proline

((1H-imidazol-4-yl)methyl)-L-proline

(1S,2R)-N1-(2-ethynylbenzyl)cyclohexane-1,2-diamine

(1S,2R)-N1-(cyclopropylmethyl)cyclohexane-1,2-diamine