We are happy to introduce ZODIAC, a tool for the comprehensive annotation of molecular formulas for complete LC-MS/MS runs. SIRIUS 4 is currently best-of-class for this task (as far as we know); but ZODIAC can do better. Different from SIRIUS which considers one compound at a time, ZODIAC considers a complete dataset, assuming that all compounds are somehow related (usually through biotransformations). See the preprint for evaluation and method details.
ZODIAC is about de novo annotations, meaning that we can assign molecular formulas for novel compounds currently absent from any structure database. ZODIAC takes into account “uncommon” elements, as in C24H47BrNO8P or C15H30ClIO5; both examples are indeed novel molecular formulas annotated by ZODIAC (and verified by us). Enter those molecular formulas into the PubChem search and see what you get back. (Fun fact: the first query now returns two entries created Jan 2020 based on our annotations.)
You can download, install and use ZODIAC through SIRIUS 4.4. Results of ZODIAC are simply displayed in the molecular formula tab, if you choose to run it. You should definitely use ZODIAC if you want to run CANOPUS: Assigning molecular classes to novel compounds implies that some of the molecular formulas may be novel, too; and you do not want provide CANOPUS a wrong molecular formula.
ps. Sorry for tweeting early, WordPress sometimes has a mind of its own.