Synthetic tranquillisers are mostly barbituric acid derivatives (e.g. veronal, luminal, seconal, amytal and nembutal). Other tranquillisers which are not barbituric acid derivatives are chlordiazepoxide, equanil meprobamate, valium (diazepam), etc. Opium alkaloids such as morphine and codeine are powerful analgesics (reduce pain). Heroin which is morphine diacetate is a widely used narcotic analgesic. Drugs which are used to cure diseases caused by microbes are called antimicrobials. These may be either sulpha drugs such as sulphapyridine, sulphadiazine, sulphaguanidine or they may be antibiotics. Antibiotics such as erythromycin, tetracycline, chloramphenicol which inhibit or arrest the growth of microbes are called bacteriostatic while others which kill the microbes are called bactericidal antibiotics.
Which of the following tranquillisers is not a derivative of barbituric acid ?

Options

A. Veronal
B. Equanil
C. Seconal
D. Luminal

Answer

To solve the question regarding which tranquilizer is not a derivative of barbituric acid, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Definition**: First, we need to understand what barbituric acid derivatives are. Barbituric acid derivatives are synthetic compounds that are derived from barbituric acid and are commonly used as tranquilizers.

2. **Identify Barbituric Acid Derivatives**: From the provided information, we can list the examples of tranquilizers that are derivatives of barbituric acid:
- Veronal
- Luminal
- Seconal
- Amytal
- Nembutal

3. **Identify Other Tranquilizers**: Next, we need to identify the tranquilizers mentioned in the text that are not derivatives of barbituric acid:
- Chlordiazepoxide
- Equanil
- Meprobamate
- Valium (Diazepam)

4. **Determine the Answer**: The question asks which tranquilizer is not a derivative of barbituric acid. From the list of tranquilizers that are not derivatives, we can see that:
- Equanil is specifically mentioned as one of the tranquilizers that is not a barbituric acid derivative.

5. **Conclusion**: Therefore, the answer to the question is **Equanil**.

### Final Answer:
Equanil is the tranquilizer that is not a derivative of barbituric acid.

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