i cycle and run a lot and actually tested this and also for other distances
you can really only compare them by feel/effort level
for me it was
100m bike steady Z2 gives me the same fatigue (overall and muscular) as 90-120min run @same effort (about 12-16m)
just metabolically or in calories it would probably be a 5h steady run...
2h @150hr bike feels the same on the body as 45min @150hr
the longer i go the bigger the gap between cycling and running equivalents is