Question

what makes chalcone and pyrazoline derivatives have different biological activity? (such as anticancer, anti-inflammatory, antioxidant etc). please explain each substituent groups that differenciate their biological activity...please enlighten me

Answer 1

• Pyrazolines derivatives show tremendous biological activities such as antimicrobial, anti-inflammatory, analgesic, antipyretic, antidepressant, antitubercular, antiamoebic, anthelmintic, anticonvulsant, antihypertensive, antidiabetic, antitumor, anti-HIV, local anaesthetic, antioxidant, insecticidalChalcones are established to be effective as antimicrobial antiviral cardiovascular and anti-inflammatory agents
• The compounds containing chloro, hydroxo and dimethylamino -N(CH₃)₂ group as substituents on the naphthalene rings have been institute very efficient antimicrobial agents. In addition, the presence of a carboxamido -CONH₂ substituent group at the N-1 position of the 2-pyrazoline rings is found to give substantially to the antimicrobial activity.
• All the pyrazolines, in general, display C=N stretching vibrations in the ν 1687-1483 cm^-1 range also shows C=C and C=O vibrations. In addition, the absorption frequencies at ν 3583-3485(s), 3456-3220(m), 1677-1630(s) and 834-815(s) representing the presence of -OH, -NH₂ >C=O and –Cl groups, in that order.
• chalcones has the occurrence of a conjugated carbonyl group (>C=O).

chalcones structure

pyrazoline structure

• the compounds with -OH and -Cl groups in combination with a -NMe₂ group as substituents on the naphthalene rings can act as very efficient antimicrobial agents . the dimethylamino (NMe₂), group exercise distinct antimicrobial activity which is independent of the presence of other substituents. carboxamido (CONH₂) group attached to the N-1 position of the pyrazoline ring presents a substantial contribution in the enhancement of antimicrobial activity