The detection of Isocyanogen (CNCN) by Agúndez, Marcelino, and Cernicharo was reported in 2018. The molecule was detected toward the dense clouds L483 and, tentatively, TMC-1 using the IRAM 30m telescope. Isocyanogen was subsequently also detected by Vastel et al. toward L1544 in 2019. The second detection also employed observations with the IRAM 30m telescope.

Isocyanogen is a less stable isomer of cyanogen, NCCN or C₂N₂, which has no dipole moment and thus cannot be detected via rotational spectroscopy. The cyano radical, CN, is sometimes (mis)identified as cyanogen as well, which has led to occasional confusion between CN and C₂N₂. Isocyanogen is one of the numerous known astromolecules that include the cyano group.