other b lactam Flashcards
What is Thienamycin?
A potent antibiotic with a carbapenam nucleus, known for its broad-spectrum antibacterial properties
Isolated from Streptomyces cattleya and active against Gram-positive and Gram-negative bacteria, including Pseudomonas aeruginosa.
What is the significance of the acylamino side chain in Thienamycin?
It is absent, which contributes to its unique properties compared to penicillins.
What is the structure of Thienamycin characterized by?
A double bond leading to high ring strain and increased β-lactam ring reactivity.
What are the key characteristics of Thienamycin?
- Potent against Gram-positive and Gram-negative bacteria
- Low toxicity
- High resistance to β-lactamases
- Poor stability in solution
Which bacteria is Thienamycin particularly effective against?
Pseudomonas aeruginosa.
What is a notable property of Thienamycin regarding β-lactamases?
It is resistant to inactivation by most β-lactamases, making it effective against resistant strains.
What is the chemical instability of Thienamycin attributed to?
Intermolecular aminolysis of the β-lactam by the cysteamine side chain of a second molecule.
What is Imipenem?
A chemically stable derivative of Thienamycin, known as N-formimidoylthienamycin.
What is the role of cilastatin when administering Imipenem?
It is a dehydropeptidase inhibitor that prevents the metabolism of Imipenem to toxic metabolites.
What are Monobactams?
A class of β-lactam antibiotics characterized by a monocyclic β-lactam ring.
What is Nocardicin A?
A monobactam that is moderately active against a narrow group of Gram-negative bacteria.
What is Aztreonam?
A clinically useful monobactam administered by intravenous injection, effective against Gram-negative bacteria.
What is the mechanism of action of Clavulanic acid?
It acts as a powerful irreversible inhibitor of β-lactamases, functioning as a suicide substrate.
What is Augmentin?
A combination of ampicillin and clavulanic acid.
What is Timentin?
A combination of ticarcillin and clavulanic acid.
What are Sulbactam and Tazobactam?
Suicide substrates for β-lactamase enzymes with broader activity than clavulanic acid.
What is Unasyn?
A combination of ampicillin and sulbactam.
What is Tazocin or Zosyn?
A combination of piperacillin and tazobactam.
