Calcium channel blockers (CCBs) are antihypertensive drugs that lower blood pressure by blocking calcium entry into heart and blood vessel cells, leading to relaxation of vascular smooth muscle. They are classified into three groups: phenylalkylamines, benzothiazepines, and dihydropyridines, with drugs like nifedipine and amlodipine for specific uses such as angina. The document covers their mechanism of action, structural activity relationships of 1,4-dihydropyridine, and physical properties of various CCBs.

1. Calcium Channel
Blockers
Presented By Mainak Saha

2. Contents
• Introduction
• Mechanism Of Action
• Classification of Calcium
Channel Blockers
• SAR OF 1,4-Dihydropyridine
• Drug Name With Structure,
IUPAC & Physical Properties
• References

3. Calcium channel blockers (CCBs) also known as
calcium antagonists.
Calcium channel blockers are drugs used to lower
blood pressure.
They work by slowing the movement of calcium
into the cells of the heart and blood vessel walls.
Therefore it easier for the heart to pump and
widens blood vessels.
As a result, the heart doesn't have to work as hard,
and blood pressure lowers.
They are first line antihypertensive drugs. They are
also used to treat angina.
Introduction

4. Calcium-channel blockers (CCBs) bind to L-type calcium
channels located on the vascular smooth muscle, cardiac
myocytes, and cardiac nodal tissue.
Mechanism Of
Action
These channels are responsible for regulating the influx of
calcium into muscle cells, which in turn stimulates smooth
muscle contraction and cardiac myocytes contraction.
In cardiac nodal tissue, L-type calcium channels play an
important role in pacemaker currents and in phase 0 of the action
potentials.
Therefore, by blocking calcium entry into the cell, CCBs cause
vascular smooth muscle relaxation (vasodilation), decreased
myocardial force generation (negative inotropy), decreased heart
rate (negative chronotropic), and decreased conduction velocity
within the heart (negative dromotropic).

5. Classification of Calcium Channel Blockers
Phenylalkylamines Benzothiazepines
Dihydropyridines
Verapamil Diltiazem
1st
Generation
2nd
Generation
3rd
Generation
Nifedipine Amlodipine
Felodipine Nicardipine Isradipine

6. SAR OF 1,4-Dihydropyridine
• 1,4-Dihydropyridine ring is essential for activity
• Substitution at nitrogen or oxidation or reduction of the ring reduce activity
• A Phenyl substitution at R4 position is essential for activity
• Ortho and meta position substitution is better for activity
• 3, 5 position ester group is essential for activity
• C-2 & C-6 methyl group is activity

7. Nifedipine
Physical
Properties-
Insoluble in water , soluble in acetone, methanol
Half life 10-18 hrs
No2 group is essential, Use in angina pectoris
Drug Name With Structure, IUPAC &
Physical Properties
Physical Properties- Slidely soluble in water , soluble in methanol
Half life 34 hrs
It has greater selectively of vascular smooth muscle
Amlodipine

8. Physical Properties- Insoluble in water , soluble in acetone
Half life 10-18 hrs
Use in angina pectoris
Felodipine

9. References 1. Selvakumar. S , J. Dighade . S, R.
Srinivasan MEDICINAL CHEMISTRY-II
2.https://www.cvpharmacology.com/vas
odilator/CCB
3. K. G. Bothara “A text book Medicinal
Chemistry – II”

10. Thank You