Question

A diuretic compound cyclothiazide has a ____ substituent at C-3 of 1,2,4- benzothioadiazine nucleus?

• A. 5-Bornen-2-yl
• B. 5-Norbornen-2-yl
• C. 2-Bornen-5-yl
• D. 2-Norbornen-5-yl

Answer 1

The Correct Option is B

The question asks about the substituent group present at the C-3 position of the 1,2,4-benzothiadiazine nucleus in the diuretic compound cyclothiazide.

The structure of cyclothiazide is derived from a chemical class known as thiazide diuretics, which are based on the 1,2,4-benzothiadiazine-1,1-dioxide skeleton. A common feature of these compounds is the presence of various substituents at different positions including the C-3 position.

The substituent at C-3 is specifically asked about, and the given options are:

1. 5-Bornen-2-yl
2. 5-Norbornen-2-yl
3. 2-Bornen-5-yl
4. 2-Norbornen-5-yl

In the case of cyclothiazide, the correct substituent at the C-3 position is 5-Norbornen-2-yl. This particular group is a bicyclic structure, which is characteristic for cyclothiazide.

Let's break down why this is the correct answer, eliminating the other options:

• 5-Bornen-2-yl and 2-Bornen-5-yl: These represent substituents found in camphor and related compounds which are not typically associated with thiazide diuretics.
• 2-Norbornen-5-yl: This is a possible isomer of the correct answer but does not correspond to the substituent used in cyclothiazide, based on known chemical literature.

Overall, the unique arrangement of atoms in 5-Norbornen-2-yl is responsible for the pharmacological activity attributed to cyclothiazide.