thumb|center|580px|Illustrative alkynes: a, acetylene, b, two depictions of propyne, c, 1-butyne, d, 2-butyne, e, the naturally occurring 1-phenylhepta-1,3,5-triyne, and f, the strained cycloheptyne. Triple bonds are highlighted blue.
thumb|center|580px|illustrative alkynes a acetylene b two depictions of propyne c 1-butyne d 2-butyne e the naturally occurring 1-phenylhepta-135-triyne and f the strained cycloheptyne triple bonds are highlighted blue