Pharmaceutical Organic Chemistry Notes – B. Pharma 4th Semester PDF Lecture Notes Free Download

Scope: This subject imparts knowledge of stereo-chemical aspects of organic compounds and organic reactions, important named reactions, and the chemistry of important heterocyclic compounds. It also emphasizes medicinal and other uses of organic compounds.

Objectives: At the end of the course, the student shall be able to

1. Understand the methods of preparation and properties of organic compounds

2. Explain the stereo-chemical aspects of organic compounds and stereo-chemical reactions

3. Know the medicinal uses and other applications of organic compounds

Course Content:

Note: To emphasize definitions, types, mechanisms, examples, uses/applications

Pharmaceutical Organic Chemistry UNIT-I

Stereo isomerism

Optical isomerism –
Optical activity, enantiomerism, diastereoisomerism, meso compounds

Elements of symmetry, chiral and achiral molecules

DL system of nomenclature of optical isomers, sequence rules, RS system of nomenclature of optical isomers

Reactions of chiral molecules

Racemic modification and resolution of a racemic mixture. Asymmetric synthesis: partial and absolute

Pharmaceutical Organic Chemistry UNIT-II

Geometrical isomerism

Nomenclature of geometrical isomers (Cis Trans, EZ, S yn Anti systems)

Methods of determination of the configuration of geometrical isomers. Conformational isomerism in Ethane, n-Butane and Cyclohexane.

Stereo isomerism in biphenyl compounds (Atropisomerism) and conditions for optical activity.

Stereospecific and stereoselective reactions

Pharmaceutical Organic Chemistry UNIT-III

Heterocyclic compounds:

Nomenclature and classification

Synthesis, reactions, and medicinal uses of the following compounds/derivatives Pyrrole, Furan, and Thiophene

Relative aromaticity and reactivity of Pyrrole, Furan, and Thiophene

Pharmaceutical Organic Chemistry UNIT-IV

Synthesis, reactions, and medicinal uses of the following compounds/derivatives Pyrazole, Imidazole, Oxazole, and Thiazole.

Pyridine, Quinoline, Isoquinoline, Acridine and Indole. Basicity of pyridine

Synthesis and medicinal uses of Pyrimidine, Purine, azepines, and their derivatives

Pharmaceutical Organic Chemistry UNIT-V

Reactions of synthetic importance

Metal hydride reduction (NaBH4 and LiAlH4), Clemmensen reduction, Birch reduction, Wolff Kishner reduction.

Oppenauer-oxidation and Dakin reaction.

Beckmann rearrangement and Schmidt rearrangement. Claisen-Schmidt condensation

Pharmaceutical Organic Chemistry III in a B. Pharma 4th Semester Short Notes:

1. Stereoisomerism: Stereoisomerism refers to the phenomenon where compounds have the same molecular formula and connectivity but differ in their spatial arrangement. It can be classified into two types: optical isomerism (enantiomers) and geometrical isomerism (cis-trans isomers).

2. Optical Isomerism: Optical isomerism arises when a compound possesses one or more chiral centers, leading to the existence of enantiomers. Enantiomers are non-superimposable mirror images of each other and exhibit different optical activities (rotation of plane-polarized light).

3. Geometrical Isomerism: Geometrical isomerism occurs when compounds have restricted rotation around a double bond or within a cyclic structure, resulting in cis-trans isomer pairs. Cis isomers have similar groups on the same side, while trans isomers have similar groups on the opposite side.

4. Heterocyclic Compounds: Heterocyclic compounds are organic compounds that contain at least one heteroatom (such as nitrogen, oxygen, sulfur) within a ring structure. They exhibit diverse biological activities and are widely used as medicinal agents. Pyrazole, imidazole, oxazole, and thiazole are examples of heterocyclic compounds.

5. Reactions and Medicinal Uses of Heterocyclic Compounds: Pyrazole, imidazole, oxazole, thiazole, pyridine, quinoline, isoquinoline, acridine, and indole are important heterocyclic compounds with varied medicinal uses. Their synthesis, reactions, and applications in drug design and development are studied in this context.

6. Basicity of Pyridine: Pyridine is a basic heterocyclic compound due to the lone pair of electrons on its nitrogen atom. It acts as a weak base and can form coordination complexes with various acids.

7. Synthesis and Medicinal Uses of Pyrimidine: Pyrimidine is a heterocyclic compound found in nucleic acids. Its synthesis and derivatives are of great interest in medicinal chemistry, as pyrimidine-based drugs have therapeutic applications in treating cancer, viral infections, and other diseases.

8. Metal Hydride Reduction: Metal hydride reduction, involving reagents like NaBH4 and LiAlH4, is a common method used for the reduction of carbonyl compounds to their corresponding alcohols. These reductions are important in the synthesis of pharmaceutical compounds.

9. Clemmensen Reduction, Birch Reduction, Wolff-Kishner Reduction: These are specific reduction reactions used to convert carbonyl compounds into alkanes. The Clemmensen reduction employs zinc amalgam and hydrochloric acid, the Birch reduction uses sodium metal and liquid ammonia, while the Wolff-Kishner reduction utilizes hydrazine and a strong base.

10. Oppenauer-Oxidation and Dakin Reaction: Oppenauer-oxidation is a selective oxidation method used to convert secondary alcohols into ketones. The Dakin reaction involves the oxidation of amino compounds, such as amino acids, to corresponding aldehydes or ketones using hydrogen peroxide and an alkali.

11. Beckmann Rearrangement and Schmidt Rearrangement: Beckmann rearrangement is a reaction that converts ketoximes into amides, while Schmidt rearrangement converts alcohols or ketones into amines using hydrazoic acid or its derivatives.

12. Claisen-Schmidt Condensation: Claisen-Schmidt condensation is a type of carbon-carbon bond formation reaction between an aldehyde or ketone and an ester or another carbonyl compound. It leads to the formation of an α,β-unsaturated compound, often used in the synthesis of various pharmaceuticals.

Pharmaceutical Organic Chemistry Recommended Books (Latest Editions)

1. Organic chemistry by I.L. Finar, Volume-I & II.

2. A text book of organic chemistry – Arun Bahl, B.S. Bahl.

3. Heterocyclic Chemistry by Raj K. Bansal

4. Organic Chemistry by Morrison and Boyd

5. Heterocyclic Chemistry by T.L. Gilchrist