PHENACEMIDE Synthesis, SAR, MCQ,Structure,Chemical Properties and Therapeutic Uses

PHENACEMIDE Synthesis, SAR, MCQ,Structure,Chemical Properties and Therapeutic Uses


IUPAC nomenclature



Phenacemide is an acetylurea derivative anticonvulsant.


Physiochemical Properties

1 Molecular weight 178.19 g/mol
2 Physical appearance White to creamy white crystalline solid.
3 Melting point 215°C
4 Solubility Very slightly soluble in water; slightly soluble I benzene, chloroform, alcohol, ether.
5 Octanol/water partition coefficient 0.87
6 Presence of ring Phenyl
7 Number of chiral centers Not present


Mechanism of Action

i. Phenacemide binds and blocks neuronal sodium channels / voltage sensitive calcium channels.

ii. This results in blockage or suppression of neuronal depolarization and hypersynchronization.

iii. Seizures cause due to hypersynchronization is controlled.


Structure Activity Relationship

SAR of phenylacylureas can be summarized as follows:

  • Branched chain aliphatic acid derivatives of urea are most active.
  • Optimum activity can be found at seven carbon atoms.
  • Increase in molecular weight results in decrease in anticonvulsant properties.
  • Increase in molecular weight further results in hypnotic activities.


Method of synthesis

Phenacemide can be synthesized by reacting 2-phenylacetyl chloride with urea.

Therapeutic Uses

Phenacemide is used for:

  • Treatment of epilepsy


Side Effects

Side effects of Phenacemide are: 

  • Dizziness
  • Drowsiness
  • Abdominal pain
  • Loss of appetite
  • Nausea
  • Vomiting
  • Headache
  • Depression
  • Suicidal thoughts
  • Mood changes
  • Signs of infections
  • Rashes
  • Rapid breathing
  • Fainting
  • Liver problems
  • Muscle pain’
  • Low blood counts
  • Weight loss



Q.1 Choose the correct statements related with the physicochemical properties of drug phenacemide.

I. Molecular weight = 178.19 gm/mol

II. It is a creamy white crystalline solid

III. Melting point is 215oC

IV. It is freely soluble in water 

a) I, III, IV

b) II, IV

c) I, IV

d) I, II, IV

Q.2 Match the following of the drugs with their correct IUPAC names.

i. Phenacemide A. 4-[bis(2-Chloroethyl)amino]-L-phenylalanine
ii. Melphalan  B. 1,1′,1′′-Phosphorothioyltriaziridine
iii. Chlorambucil C. 4-[bis(2-chlorethyl)amino]benzenebutanoic acid
iv. Thiotepa D. N-Carbamoyl-2-phenyl-acetamide

 a) i-C, ii-A, iii-B, iv-D

b) i-D, ii-A, iii-C, iv-B

c) i-D, ii-A, iii-B, iv-C

d) i-A, ii-C, iii-B, iv-D

Q.3 Correct steps for the mechanism of action of the drug Phenacemide are?

I. Suppression of neuronal depolarizatioon

II. Stimulation of neuronal depolarization

III. Blocking of neuronal sodium channel

IV. Agonistic effect on neuronal sodium channels

a) I – III

b)II – III

c) III – I

d) IV- II

Q.4 Correct sequence for True/false for the classification of the drug can be?

  • Phenacemide: Anticonvulsant drug
  • Pilocarpine: Muscarnic agonist
  • Scopolamine: Acetylcholine antagonist
  • Pancuronium: Nicotinic antagonist





Q.5 Increase in weight of phenylacylureas leads to?

a) Increase in anticonvulsant properties

b) Decreases in anticonvulsant properties

c) No changes in anticonvulsant activity

d) Unpredictable changes

Q.6 The two chemicals which on reaction with each other produces Phenacemide?

I. 2-phenylacetyl chloride

II. 3-hydroxy-butanoyl chloride

III. Urea

IV. Aniline

a) II, IV

b) II, IV

c) I, III

d) I, II 

Q.7 Side effect of drug phenacemide include?

a) Abdominal pain

b) Liver problems

c) Low blood counts

d) All of the above


For More Standard and Quality Question Bank you can Join Our Test Series Programme for GPAT, NIPER JEE, Pharmacist Recruitment Exam, Drug Inspector Recruitment Exams, PhD Entrance Exam for Pharmacy

Participate in Online FREE  GPAT  TEST: CLICK HERE

  Participate in Online FREE  Pharmacist  TEST: CLICK HERE 

Participate in Online FREE  Drug Inspector  TEST: CLICK HERE 













[1] Vardanyan R, Hruby V. Synthesis of essential drugs. Elsevier; 2006 Mar 10.

Leave a Reply

Your email address will not be published. Required fields are marked *

five × 2 =

Free Video Lectures of Pharmacy Exams
Apply now

Developed By Connect Globes