  We report for the first time the occurrence of superconductivity in the
quaternary silicide carbide YRe2SiC with Tc = 5.9 K. The emergence of
superconductivity was confirmed by means of magnetic susceptibility, electrical
resistivity, and heat capacity measurements. The presence of a well developed
heat capacity feature at Tc confirms that superconductivity is a bulk
phenomenon, while a second feature in the heat capacity near 0.5 Tc combined
with the unusual temperature dependence of the upper critical field Hc2(T)
indicate the presence of a multiband superconducting state. Additionally, the
linear dependence of the lower critical field Hc1 with temperature resemble the
behavior found in compounds with unconventional pairing symmetry. Band
structure calculations reveal YRe2SiC could harbor a non-trivial topological
state and that the low-energy states occupy multiple disconnected sheets at the
Fermi surface, with different degrees of hybridization, nesting, and screening
effects, therefore making unconventional multiband superconductivity plausible.
