Table 1: Log of experiments for GC-MS analysis.

Experiment	Ice	UV dose	Molecular ion mass	Assigned carrier	Integ. area
	H2O:NH3:CH3OH:CO:CO2	photon molec.-1	amu		(relat. to HMT)
1	2:1:1:1:1	0.15	140	HMT	100
			154	HMT-CH3	0.005
			156	HMT-OH	0.04, 0.02
			198	HMT-CHOH-CHO	0.04
2	2:1:1:1:12	0.45	144	HMT	100
			160	HMT-OH	2.0
3	2:1:1:1:13	0.28	140, 141, 142, 143, 144	HMT	100
			156, 157, 158, 159	HMT-OH	4.0
4	2:1:1:0:1	0.15	140	HMT	100
			154	HMT-CH3	0.07
			156	HMT-OH	0.25
			170	HMT-CH2OH	0.03
			183	HMT-NH-CHO	0.04
5	2:1:1:0:14	0.15	146	HMT	100
			161	HMT-CH3	0.021
			162	HMT-OH	1.2
			177	HMT-CH2OH	0.3
			190	HMT-NH-CHO	0.1
6	2:0.2:1:0:1	0.28	140	HMT	100
			154	HMT-CH3	0.01
			156	HMT-OH	0.20
			198	HMT-CHOH-CHO	0.07
7	2:1:1:1:14,5	0.45	146	HMT	100
			161	HMT-CH3	0.4
			162	HMT-OH	12
			206	HMT-CHOH-CHO	2.0

1 Using hexane as solvent, undetected in methanol solution. 2 15NH3-labelled. 3 With 13CO, 13CO2, 12CH3OH. 4 13C-labelled. 5 Using DMF-DMA derivatization.