The most useful classification of drugs form for medicinal chemists is.

Options

A. On the basis of chemical structure
B. On the basis of drug action
C. On the basis of molecular targets
D. On the basis of pharmacological effect

Answer

### Step-by-Step Solution:

1. **Understanding Drug Classification**: Drugs can be classified in various ways, including their chemical structure, drug action, molecular targets, and pharmacological effects. Each classification serves a different purpose in medicinal chemistry.

2. **Chemical Structure**: This classification focuses on the molecular composition of the drug. While important, it does not directly relate to how the drug interacts with biological systems.

3. **Drug Action**: This classification looks at how the drug performs in the body. It is useful but does not provide insight into the specific interactions at the molecular level.

4. **Molecular Targets**: This classification is based on the specific receptors or enzymes that the drug interacts with in the body. Understanding molecular targets is crucial for medicinal chemists as it directly relates to the drug's mechanism of action and efficacy.

5. **Pharmacological Effect**: This classification considers the overall effects of the drug on the body after it binds to its target. While this is important, it is the interaction with molecular targets that determines the pharmacological effect.

6. **Conclusion**: Based on the above analysis, the most useful classification of drugs for medicinal chemists is on the basis of **molecular targets**. This classification helps in understanding how drugs work at a molecular level and guides the design of new drugs.

### Final Answer:
The most useful classification of drugs for medicinal chemists is **on the basis of molecular targets**.

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