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Clinical pharmacy PharmD program Third level Phytochemistry-1 (PG-504)

2. Amikacin

Amikacin is made semi-synthetically from kanamycin.

• Hydroxyaminobutyl (HABA) moiety strongly enhanced the potency and

spectrum,

• So amikacin is used competitively with gentamicin for the treatment of sensitive

strains of mycobacterium tuberculosis and severe Pseudomonas aeruginosa

infections resistant to other drugs.

• No oral form available as amikacin is not absorbed orally.

• In people with kidney failure, dosage must be reduced according to the

creatinine clearance.
II. Having carbohydrate as small part of the molecule but is essential:

Macrolide antibiotics: (e.g: Erythromycins)

• According to the ring size of the aglycone, the macrolide antibiotics are

classified as either 12-, 14-, or 16-membered ring macrolides.

• 10 – 16 ring members are very strongly antibacterial

• 16 – 40 ring members show very little activity against bacteria, often none

at all, but they are highly effective against fungi, yeasts, etc.

• The very large macrolides are highly effective against fungi and viruses.

Till now, more than 90 macrolides have been discovered. The change in the

antibiotic activity spectrum is due to:

o Changes in the ring size

o The substituents

o The degree of unsaturation.

14-Membered Ring Macrolides: Erythromycins

Erythromycins A, B, C and D are produced by Streptomyces erythreus.

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