Podcast
Questions and Answers
What is the primary reason for the loss of activity of tetracycline (TC) at pH less than 2?
What is the primary reason for the loss of activity of tetracycline (TC) at pH less than 2?
- Formation of the anhydrotetracycline structure
- Modification of the hydroxyl group on C6 by strong acids
- Cleavage of the lactone ring forming isotetracycline
- Elimination of a water molecule and aromatization of ring C (correct)
What structural change occurs when TC is treated with bases?
What structural change occurs when TC is treated with bases?
- Cleavage of the bond between atoms 11 and 11a, forming the lactone ring (correct)
- Formation of the anhydrotetracycline structure
- Modification of the hydroxyl group on C6 by strong bases
- Elimination of a water molecule and aromatization of ring C
Which statement about anhydrotetracycline is correct?
Which statement about anhydrotetracycline is correct?
- It has the same molecular and structural formula as TC
- It is formed by the action of strong acids on TC
- It differs from TC in both molecular and structural formula and is inactive as an antibacterial (correct)
- It is formed by the action of strong bases on TC
Which of the following compounds has the same molecular formula as TC but a different structural formula and is inactive?
Which of the following compounds has the same molecular formula as TC but a different structural formula and is inactive?
In the base colorimetric method for tetracycline and oxytetracycline, what is the absorption maximum of the yellow color produced by the addition of alkali?
In the base colorimetric method for tetracycline and oxytetracycline, what is the absorption maximum of the yellow color produced by the addition of alkali?
What is the disadvantage of the base colorimetric method for tetracycline and oxytetracycline?
What is the disadvantage of the base colorimetric method for tetracycline and oxytetracycline?
Which of the following statements about chlortetracycline is correct in the base colorimetric method?
Which of the following statements about chlortetracycline is correct in the base colorimetric method?
What is the primary reason for the decrease in intensity of the yellow color over time in the base colorimetric method for tetracycline and oxytetracycline?
What is the primary reason for the decrease in intensity of the yellow color over time in the base colorimetric method for tetracycline and oxytetracycline?
