Pyridine

 

This is a clear, slightly yellowish liquid, having an unpleasant and penetrating odor (sour, putrid and evoking fish).

Pyridoxal

Vitamin B6

wherefrom derives

Pyridoxal phosphate, which is an essential coenzyme in a significant number of reactions of amino acids (transaminations, decarboxylations and racemizations)

Nicotine

(S)-3-(1-methyl-pyrrolidin-2-yl)pyridine

Alkaloid present in the leaves of Nicotiana tabacum

Stimulating, relaxing and very addictive drug, especially in conjunction with other substances present in cigarette smoke. Facilitates the development of cancers. Formerly used as a pesticide.

Nicotinamide

Pyridin-3-carboxamid

essential constituent of both coenzymes of tissue dehydrogenations $NAD^+$ (Nicotinamide adenine dinucleotide) and $NADP^+ $ (Nicotinamide adenine dinucleotide phosphate) These substances are capable of fixing hydrogen reversibly.

Nikethamide

"Coramine"

Cardiovascular stimulant, it is on the list of substances banned by the Doping Code

Isoniazid

"Rimifon"

Antibiotic used in the treatment of tuberculosis

Mycobacterium tuberculosis

Image due to →   Muhsin Özel, Gudrun Holland / RKI