Unknown compound identification (quant mass 278) February 22, 2021, 09:39:24 AM Hey Everyone,when I saw the title of this section I was sure that my request fits in here. After reading some of the other post I became sceptical but still I would like to place my question somewhere. I found some interesting Peaks in my GC-EI-TOF data (MEOX + TMS derivatized polar extracts of natural microbial communities) and the library's couldn't help in understanding the compound I found here. The RI of the requested analyte is 2003.3 and I have a very similar spectrum occuring at RI 2055.2. It seems to me that there one analyte with different configurations (like the sugars) but m/z 278 is a black box for me. Does anyone knows which fragment m/z 278 typically represents? Or can someone help me with the compound class?You can find the spectrum table of this compound attached to this post. Many thanks for any comment!Stefan