B LACTAM ANTIBIOTICS,PENICILLIN PPT.

1. GITANJALI COLLEGE OF PHARMACY
NAME: MD KAIF ALI
UNIVERSITY ROLL: 36201921011
REG. NO: 213620201910015 OF 2021
SUBJECT: MEDICINAL CHEMISTRY III (PT-613)
B.PHARM 3RD YEAR 6TH SEM
SESSION: 2021 - 25
INTERNAL
ASSESSMENT (CA-1)

2. TITLE : BASIC INTRODUCTION OF
ANTIBIOTICS AND VARIOUS
CLASSIFICATION OF ANTIBIOTICS
CONTENTS
 Antibiotics
 History of antibiotics
 Classification Of Antibiotics
 Classification Of β –lactum antibiotics
 Penicillins
 Classification Of Penicillins

3. INTRODUCTION OF ANTIBIOTICS
• What is Antibiotics ?
 This are those chemical substance which are
obtained from various species of
microorganism that kill or inhibit the growth
of another microorganism in low
concentration .
• What actually antibiotics do ?
 Mainly kill or inhibit the growth of bacteria.

4. Difference Between Antibiotics and
Antibacterial
Antibiotics
1. Kill or inhibit the growth of
bacteria
2. Only for medicinal purpose
3. Mainly obtained from
microorganism
Antibacterial
1. Kills or inhibit bacteria
2. Also include soap detergent
disinfectants etc.

5. History of antibiotics
 In anclent times, there are difficulties in treatment of infectious disease.
 Mainly use for infection is plant and animal,molding bread and chease.
 Firstly the term “common bacteria” is turmed by Louis Pasteur in 1877.
 In1929,Sir Alexander Flemming accidentally discovered the first antibiotic
“penicillin” by destroying the staphylococcus in culture plate.
 In 1942 ,the word antibiotics was used by Selman waksman.
 Paul ehrlich find a cure for cycles in 1909 ,He is called father of modern
chemotherapy.
Further Discovery
 Tyrothricin-1939
 Streptomycin-1943
 Chloramphenicol-1948
 Neomycin-1949
 Erythromycin-1952

6. CLASSIFICATION OF ANTIBIOTICS
• According to their spectrum :
 Broad Spectum: Those types of antibiotics wide range of action and
inhibit or kills both type of bacteria such as gram negative and gram
positive
 Narrow spectrum: Those type of antibiotics have short range of action
and inhibit or kill only on type of bacteria gram positive or gram
negative
 Example: Penicillin- G,Steptomycin etc.
 According to their origin sources:
 Natural antibiotics: Those types of antibiotics which obtain from
naturally from microrganism
Example: fermentation of microbes
 Semisynthetic antibiotics: Those types of antibody which mainly
obtained from naturally with mixture of some chemical substance
Example: penicillin V etc.
 Synthetic antibiotics: Those types of antibiotics obtain purely synthetic.
Example: Chloramphenicol etc.

7. According to their mechanism action:
 Drug that interface with the synthesis of bacterial cell wall
Example: Penicillin,Cephalosporins,Cycloserine etc
 Drug that interface with the functioning of cytoplasmic membrane
Example: Amphotericin B , Nystatin etc.
 Drug that interface with the protein synthesis
Example: Tetracycline,Erythromycin,Chloramphenicol.
 Drug that interface with the nucleic acid biosynthesis.
Example- Actinomycin,Rifampin etc.
According to their Chemical Structure:
1. B-lactam Antibiotics - Penicillin, Cephalosporins, Monobactams
2. Aminoglycosides - Streptomycin, Neomycin , Kanamycin
3. Tetracycline-Tetracycline,Oxytetracycline,Chlortetracycline ,
Minocycline , Doxycycline
4. Macrolide- Erthromycin,Clarithromycin,Azithromycin
5. Miscellaneous- Chloramphenicol,Clindamycin

8. ΒETA LACTUM ANTIBIOTICS
 β- lactam is a cyclic amide with four atoms (3-
C&1-N) in its ring named as azetidinone.
 β -lactam antibiotics are a class of antibiotics
which contain a β-lactam ring and mainly give
their actions by inhibiting the cell wall synthesis of
bacteria.
 Example - Penicillin and it's derivatives (Penams)
Cephalosporins and it's derivatives (cephems )
MonobactamsCarbapenems

9. CLASSIFICATION OF β -LACTAM ANTIBIOTICS

10. Penicillins
Penicillin it is the first antibiotic
which first discovered and reported
in 1929 by sir Alexander Fleming.
All penicillin composed of the 6
amino penicillinic acid
nucleus with side chain.
Basic Structure of Penicillin
Fig. 1.1. Basic Structure of Penicillin

11. MECHANISM OF ACTION
• Penicillins are bactericidal antibiotics as they kill the
microorganisms when used at therapeutic dose.
• The synthesis of cell wall of bacteria is completely
depended upon an enzyme named as transpeptidase.
• Primarily, Penicillin inhibits the cell wall of bacteria by
blocking transpeptidase after binding to penicillin-
binding protein (PBP) and prevents its synthesis.
• Result: bacteria cells die from cell lysis.
• Penicillins do not kill other cells in the body.

14. REFERENCES
• A Textbook Of Medicinal Chemistry By V Alagarsamy ,CBS Publishers
,Fourth Edition
• Image-
• Fig.1.1- https://www.researchgate.net/figure/General-structure-of-
penicillins-However-another-beta-lactam-antibiotic-
Cephalosporin_fig1_324872638