Recently, the evidence for presence of E -1-cyano-1,3butadiene was reported from the dark prestellar cloud TMC-1 . Since 1,3-butadiene does not have a dipole moment, it cannot be directly observed in astrophysical environments, and the use of its cyano derivative (E -1cyano-1,3-butadiene) is suggested for indirect estimation of its concentration in this molecular cloud . As 1,3butadiene plays a crucial role in formation of the first 6-membered carbon ring molecule , this makes it one of the most important hydrocarbon molecule of the inter-stellar medium. This molecule is believed to be the precursor for formation of cyanobenzene, the simplest aromatic nitrile, which was detected in TMC-1 few years ago .