Table 1

Structure of aminoguanidines and isothioureas

Aminoguanidines

R₁	R₂
(1) Aminoguanidine	H	H
(2) 1-Methyl-aminoguanidine	CH₃	H
(3) 2-Methyl-aminoguanidine	H	CH₃
(4) 2-Ethyl-aminoguanidine	H	CH₃CH₂
(5) 2-Hydroxy-aminoguanidine	H	OH
(6) 2-Phenyl-aminoguanidine	H	C₆H₅

Isothioureas


	R₁	R′₁	R₂	R₃
(7) 1-Amino-S-methyl ITU	NH₂	H	CH₃	H
(8) 1-Amino-1-methyl-S-methyl ITU	NH₂	CH₃	CH₃	H
(9) 1-Amino-3-methyl-S-methyl ITU	NH₂	H	CH₃	CH₃
(10) S-Ethylisothiourea	H	H	CH₃CH₂	H
(11) S-Isopropylisothiourea	H	H	(CH₃)₂CH	H