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  2. Pyrrole - Wikipedia

    en.wikipedia.org/wiki/Pyrrole

    Pyrrole is a heterocyclic, aromatic, organic compound, a five-membered ring with the formula C 4 H 4 NH. [3] It is a colorless volatile liquid that darkens readily upon exposure to air. Substituted derivatives are also called pyrroles, e.g., N -methylpyrrole, C 4 H 4 NCH 3 .

  3. Heterocyclic compound - Wikipedia

    en.wikipedia.org/wiki/Heterocyclic_compound

    For example, with the benzo-fused unsaturated nitrogen heterocycles, pyrrole provides indole or isoindole depending on the orientation. The pyridine analog is quinoline or isoquinoline, and the class of analogues with two nitrogen atoms is known as the benzodiazines. For azepine, benzazepine is the preferred name.

  4. Tetrapyrrole - Wikipedia

    en.wikipedia.org/wiki/Tetrapyrrole

    Tetrapyrroles are a class of chemical compounds that contain four pyrrole or pyrrole-like rings. The pyrrole/pyrrole derivatives are linked by (= (CH)-or -CH 2-units), in either a linear or a cyclic fashion. Pyrroles are a five-atom ring with four carbon atoms and one nitrogen atom.

  5. Paal–Knorr synthesis - Wikipedia

    en.wikipedia.org/wiki/Paal–Knorr_synthesis

    Pyrrole Ring. The Paal–Knorr reaction is quite versatile. In all syntheses almost all dicarbonyls can be converted to their corresponding heterocycle. R2 and R5 can be H, aryl or alkyl. R3 and R4 can be H, aryl, alkyl, or an ester. In the pyrrole synthesis (X = N), R1 can be H, aryl, alkyl, amino, or hydroxyl. [9]

  6. Indole - Wikipedia

    en.wikipedia.org/wiki/Indole

    Indole is an organic compound with the formula C 6 H 4 CCNH 3.Indole is classified as an aromatic heterocycle.It has a bicyclic structure, consisting of a six-membered benzene ring fused to a five-membered pyrrole ring.

  7. Heme - Wikipedia

    en.wikipedia.org/wiki/Heme

    It is composed of four pyrrole rings with 2 vinyl and 2 propionic acid side chains. [1] Heme is biosynthesized in both the bone marrow and the liver. [2] Heme plays a critical role in multiple different redox reactions in mammals, due to its ability to carry the oxygen molecule.

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  9. Porphyrin - Wikipedia

    en.wikipedia.org/wiki/Porphyrin

    Brilliant crystals of meso-tetratolylporphyrin, prepared from 4-methylbenzaldehyde and pyrrole in refluxing propionic acid. A common synthesis for porphyrins is the Rothemund reaction, first reported in 1936, [12] [13] which is also the basis for more recent methods described by Adler and Longo. [14]