[phenixbb] Syntax help: phenix.pdb_tools to remove selected bases from file

Hi everyone, I am trying to truncate an RNA chain to backbone only using phenix.pdb tools with this command: phenix.pdbtools input.cif remove="(chain IN and not (phosphate or ribose)" I get: AtomSelectionError: RuntimeError: Atom selection syntax error at word "phosphate". Atom selection string leading to error: (chain IN and not (phosphate or ribose) Based on https://phenix-online.org/documentation/reference/atom_selections.htmlhttps://phenix-online.org/documentation/reference/atom_selections.htmlI I thought “phosphate” and “ribose” should be valid selection key words, but can’t figure out what I am doing wrong and would appreciate your help : ) Thanks in advance and best wishes, Matthias