We have used the Australia Telescope Compact Array to conduct a search for the simplest amino acid , glycine ( conformers I and II ) , and the simple chiral molecule propylene oxide at 3-mm in the Sgr B2 LMH .
We searched 15 portions of spectrum between 85 and 91 GHz , each of 64 MHz bandwidth , and detected 58 emission features and 21 absorption features , giving a line density of 75 emission lines and 25 absorption lines per GHz stronger than the 5 \sigma level of 110 mJy .
Of these , 19 are transitions previously detected in the interstellar medium , and we have made tentative assignments of a further 23 features to molecular transitions .
However , as many of these involve molecules not previously detected in the ISM , these assignments can not be regarded with confidence .
Given the median line width of 6.5 km/s in Sgr B2 LMH , we find that the spectra have reached a level where there is line confusion , with about 1/5 of the band being covered with lines .
Although we did not confidently detect either glycine or propylene oxide , we can set 3 \sigma upper limits for most transitions searched .
We also show that if glycine is present in the Sgr B2 LMH at the level of N = 4 \times 10 ^ { 14 } cm ^ { -2 } found by Kuan et al .
( 2003 ) in their reported detection of glycine , it should have been easily detected with the ATCA synthesized beam size of 17.0 x 3.4 arcsec ^ { 2 } , if it were confined to the scale of the LMH continuum source ( < 5 arcsec ) .
This thus puts a strong upper limit on any small-scale glycine emission in Sgr B2 , for both of conformers I and II .