Pharmaceutical Chemistry for D.Pharmacy Year 1

Pharmaceutical Chemistry (ER20-12T) deals with the chemical properties, purity, and analysis of drugs and pharmaceutical substances.

Core Topics

1. Inorganic Pharmaceutical Chemistry

Gastrointestinal Agents

  • Antacids: Sodium Bicarbonate, Aluminium Hydroxide, Magnesium Hydroxide, Calcium Carbonate
  • Mechanism: Neutralize gastric acid
  • MOA: HA + Base → Salt + H2O

    • Electrolytes

  • Sodium Chloride, Potassium Chloride
  • Used for fluid and electrolyte balance
  • Normal saline = 0.9% NaCl

    • Haematinics

  • Ferrous Sulfate, Ferrous Gluconate — for iron-deficiency anemia
  • Folic Acid — pregnancy anemia prevention

    • 2. Organic Pharmaceutical Chemistry

    Important Drug Groups

    Drug ClassRepresentativeKey Feature |------------|---------------|-------------| SulfonamidesSulfadiazinePara-amino group AntitubercularIsoniazid (INH)Isonicotinic acid hydrazide AntimalarialsChloroquineQuinoline ring Local AnestheticsLignocaineAmide linkage BarbituratesPhenobarbitoneBarbituric acid ring

    3. Medicinal Chemistry Basics

    Structure-Activity Relationship (SAR)

  • How changes in chemical structure affect pharmacological activity
  • Example: Para position substitution in sulfonamides increases antibacterial activity

    • Drug Stability

  • Hydrolysis: Most common degradation
  • Oxidation: Ascorbic acid, catecholamines
  • Light degradation: Nifedipine, Tetracycline

    • 4. Analytical Methods (Indian Pharmacopoeia)

    Physical Tests

  • Melting Point: Identity and purity test
  • Solubility: In water, alcohol, ether
  • Color & Odor: Identification

    • Chemical Tests

  • Acid-base titration
  • Redox titration
  • Precipitation reactions

    • Common Limit Tests in IP

  • Arsenic limit test
  • Chloride limit test
  • Sulfate limit test
  • Heavy metal test

    • Official Books You Should Know

  • Indian Pharmacopoeia (IP): Official standard for drugs in India
  • British Pharmacopoeia (BP): UK standard
  • United States Pharmacopeia (USP): US standard
  • Extra Pharmacopoeia (Martindale): Reference for drug information

    • FAQ

    Q: What is the Indian Pharmacopoeia (IP)? A: Official book that specifies standards for drugs, excipients, and medical devices in India. Published by IPC.

    Q: What is SAR in pharmaceutical chemistry? A: Structure-Activity Relationship — how molecular structural changes affect drug activity.

    Q: What is a limit test in pharmacy? A: Tests to confirm that certain impurities are within acceptable limits (e.g., Arsenic limit test, Chloride limit test).

    Q: What is the most common form of drug degradation? A: Hydrolysis — especially for esters and amides in aqueous formulations.

    Q: What is the significance of melting point in pharmacy? A: Indicates purity of a substance. Pure substances have sharp, defined melting points. Impurities lower and broaden the melting point range.