In this study, it was aimed to synthesize novel molecules containing potential biological active phenolic Mannich base moiety and evaluate the inhibition properties against alpha-glycosidase (alpha-Gly) and acetylcholinesterase (AChE). For this purpose, phenolic aldehydes (1-3) were synthesized from 4-hydroxy-3-methoxy benzaldehyde (vanillin) according to the Mannich Reaction. Five different carboxylic acid hydrazides (4a-e) were synthesized from esters obtained from carboxylic acids. Fifteen Schiff base derivatives (5a-e, 6a-e, and 7a-e) were synthesized from the condensation reaction of compounds 1-3 with 4a-e. In this work, a series of novel Schiff bases from Phenolic Mannich bases (5a-e, 6a-e, and 7a-e) were tested toward alpha-Gly and AChE enzymes. Compounds 5a-e, 6a-e, and 7a-e showed Kis in ranging of 341.36 +/- 31.84-904.76 +/- 93.56 nM on AChE and 176.27 +/- 22.87-621.77 +/- 69.98 nM on alpha-glycosidase. Finally, novel compounds were found using molecular docking method to calculate the biological activity of these bases against many enzymes. The enzymes used in these calculations are acetylcholinesterase and alpha-glycosidase, respectively. Molecule 6b is more effective and active than other molecules with a docking score parameter value of - 8.77 against AChE enzyme and 6d is more effective and active than other molecules with a docking score parameter value of - 4.94 against alpha-Gly enzyme. After calculating the biological activities of novel compounds, ADME/T analysis parameters were examined to calculate the future drug use properties.