Table 2 The chemical and physical properties of investigated inhibitors

HM-1221

F.wt. = C₁₈H₁₆N₂O₇

M.wt = 372.33

Yield = 69%

Shape: Red powder

M.P. = 296–298

HM-1222

F.wt. = C₁₈H₁₆N₂O₆S

M.wt = 388.39

Yield = 78%

Shape: Dark Red powder

M.P. = 280–282

HM-1223

F.wt. = C₂₂H₂₄N₂O₆S

M.wt = 444.50

Yield = 73%

Shape: Reddish brown powder

M.P. = 178–179

HM-1224

F.wt. = C₂₀H₂₀N₂O₇

M.wt = 400.39

Yield = 71%

Shape: Orange powder

M.P. = 240–242