(S)-2-Amino-N-((S)-1-benzyl-piperidin-3-yl)-N-methyl-propionamide

(S)-2-Amino-N-((R)-1-benzyl-pyrrolidin-3-yl)-3-methyl-butyramide

(S)-2-Amino-N-(1-benzyl-piperidin-3-yl)-3-methyl-butyramide

(S)-2-Amino-N-(1-benzyl-pyrrolidin-2-ylmethyl)-3,N-dimethyl-butyramide

(S)-2-Amino-N-((R)-1-benzyl-piperidin-3-yl)-N-isopropyl-3-methyl-butyramide

(S)-2-Amino-N-(1-benzyl-piperidin-3-yl)-N-cyclopropyl-3-methyl-butyramide

((R)-1-Acetyl-pyrrolidin-3-ylamino)-acetic acid

[((S)-1-Acetyl-pyrrolidin-2-ylmethyl)-amino]-acetic acid

2-[{(1-Acetyl-piperidin-3-yl)methyl}amino]acetic acid

[((R)-1-Acetyl-pyrrolidin-3-yl)-ethyl-amino]-acetic acid

(1R,4R)- [(4-Acetylamino-cyclohexyl)-ethyl-amino]-acetic acid