Question

Number of compounds among the following which contain sulfur as a heteroatom is ___.
Compounds: Furan, Thiophene, Pyridine, Pyrrole, Cysteine, Tyrosine

Answer 1

Correct Answer: 2

In the context of chemistry, a heteroatom is an atom in a ring structure that is not carbon and is often responsible for various chemical properties of the molecule. Here, we need to identify compounds from the given list that contain sulfur as a heteroatom. 

1. Furan: A five-membered heterocyclic compound with oxygen as the heteroatom. Does not contain sulfur.
2. Thiophene: A five-membered heterocyclic compound with sulfur as the heteroatom. Contains sulfur.
3. Pyridine: A six-membered heterocyclic compound with nitrogen as the heteroatom. Does not contain sulfur.
4. Pyrrole: A five-membered heterocyclic compound with nitrogen as the heteroatom. Does not contain sulfur.
5. Cysteine: An amino acid with a thiol group (-SH). Contains sulfur.
6. Tyrosine: An amino acid with a phenolic group. Does not contain sulfur.

After evaluation, the compounds Thiophene and Cysteine contain sulfur as a heteroatom. As such, the number of compounds with sulfur as a heteroatom is 2.

The expected range is 2,2, which confirms that our calculated result of 2 fits this range.

Answer 2

The compounds containing sulfur as a heteroatom are:

• Thiophene - Contains sulfur in its five-membered aromatic ring.
• Cysteine - Contains sulfur in the form of a thiol group (-SH).

Thus, the correct count of compounds with sulfur as a heteroatom is:

So, the correct option is:2