Primary curated chemical record CHEBI:16552: definition, structure, neutral-acid formula C6H11NO3S and conjugate-base relation CHEBI:57809. N-formylation modifies the amino nitrogen. Free-acid formula must not be assigned unchanged to a tRNA-bound residue.

Primary university profile headed Richard M. Caprioli, with a representative-publications list using the Caprioli RM byline and a linked portrait asset. Used for the fuller displayed name and research association, not for an assertion that every position listed on this undated page remains current.

Primary database record37_269, NIST Standard Reference Database106. Original Measurements field: H. D. Nelson and C. L. De Ligny, Recueil des Travaux Chimiques des Pays-Bas87 (1968), 528–544. The Experimental Data and Method/Apparatus/Procedure fields report nonzero hexane-in-water solubility measurements and describe overnight shaking, microsyringe sampling of the aqueous solution and gas chromatography with flame-ionization detection. Malformed columns in the displayed table are not used for a numerical composition claim.

PLOS ONE 17, e0271025 (7 July 2022), DOI 10.1371/journal.pone.0271025. Primary byline Daryl Wilding-McBride verified. Isotope-intensity inference section and Figures 7–10: saturated isotopic signals reconstructed from an unsaturated isotope under a peptide-distribution model. The article does not adopt the study’s raw-intensity saturation threshold as a universal detector limit.

Analytical Chemistry 69(23), 4751–4760 (1997), DOI 10.1021/ac970888i. Primary indexed byline R M Caprioli retained without inferred expansion. Abstract: matrix-coated tissue or tissue imprint, spatially ordered spectra and selected-ion maps; insulin localization in rat pancreatic tissue is one demonstrated example. No universal detection limit or clinical interpretation inferred.

Institutional primary teaching documentation, Steam distillation introduction and apparatus photo/assembly description: boiling flask with material and water, distillation head, condenser and receiver. Supports apparatus and thermally sensitive volatile-compound motivation; hypothetical partial pressures in the article are explicitly invented.

Journal of Mass Spectrometry 52, 580–590 (2017), DOI 10.1002/jms.3964. Primary full byline Stefan Meyer verified on page 580; this is the instrument researcher, not a historical namesake. Page 582, equation 2, writes mass/charge as k0(t−t0)^2; calibration fits identified isotopes. Only timing/mass-model statements used, no general accuracy benchmark asserted.

Official terminology entry Q04971, DOI 10.1351/goldbook.Q04971. Primary definition: selected mass/charge follows stable trajectories in combined static and high-frequency quadrupole electric fields; other values have unstable trajectories. Indexed primary plain/PDF record verified; interactive HTML fetch unavailable. Cites IUPAC Recommendations 1991, PAC 63, 1541, definition on page 1545. No quantitative transmission or resolution claim.

Manufacturer primary technical documentation, Overview of Detector System; Structure of Electron Multiplier; Electron Multiplication; Gain of Electron Multiplier; Conversion Dynode. Describes conversion to electrons and staged secondary emission, discrete/continuous dynodes and gain dependence on applied electric potential differences. No performance benchmark or operating settings transferred.

CID1024, formula C14H6N2O8, structure with adjacent quinone carbonyls and three carboxylic acid groups. Identity and connectivity only; database role annotations are not treated as evidence of human dietary essentiality.

CID9285, formula C14H14N2O4S, component/structure fields: methylphenazinium cation with methyl sulfate counterion.

NCBI PubChem CID10541, structure/SMILES COP(=O)(OC)OC and molecular formula C3H9O4P. Neutral trimethyl ester of phosphoric acid. Only identity and connectivity used; no toxicity or exposure recommendations inferred.

Primary curated record CHEBI:57917, definition, formula, net charge and conjugate-acid/base relations: C6H4NO3 with net charge −1, conjugate base of 4-nitrophenol. The general examples do not assume a universal pKa or transfer the record’s pH statement to all solvents.

SRD 69, Phenol, 4-nitro-, CAS 100-02-7. Formula, chemical-structure and alternative-name fields establish the para-substituted phenol and formula C6H5NO3; not a source for the aqueous assay coefficient.

NCBI PubChem CID378, structure, molecular formula C6H6NO6P, and description of monoesterification of phosphoric acid with4-nitrophenol. CID378 describes the neutral acid; salts/hydrates have different formula masses. Identity/structure record reused for assay-substrate definition, not as an original enzyme experiment.

Recommendations1976; primary republication with sections1 Phosphoric esters and4 Phosphodiesters. Biochemical Journal171,1–19(1978), among the publication versions listed on the official text. Section1 comment(i) prefers phosphoric ester as the generic name. Existing common wording phosphate ester retained as an EMPTY synonym, not a second concept. No personal authorship inferred.

Additional locators: §§1–4 and Table3, esters, ionic forms, anhydrides, phosphate-diester bridges and cyclic phosphates.

Additional verified locator: §3 and Table2 classify anhydrides, mixed anhydrides and ATP linkages.

Nobel Lecture, December 11, 1954; printed p.433 discusses the measured amide C–N length, partial double-bond character and planarity, and explains resonance structures as hypothetical components rather than separately synthesizable forms. Primary indexed PDF passage verified; direct PDF retrieval returned403. No quantitative rotational barrier inferred.

Primary chemical-component record WO4: name TUNGSTATE(VI)ION and formula O4W. Charge/formula corroboration PubChem CID24465 pubchem.ncbi.nlm.nih.gov/compound/Tungstate . No claim that every solid tungstate has the geometry of an isolated anion.

Primary terminology entry S05434, DOI10.1351/goldbook.S05434; localized two-centre sigma/pi symmetry definitions and distinction from whole-molecule orbital symmetry. Official indexed entry and official PDF goldbook.iupac.org/terms/view/S05434/pdf verified; direct HTML fetch returned403. Definition authority, not an experimental bond-energy measurement.

Provider-curated (S)-malate(2-): S configuration, formula C4H4O5, net charge-2, conjugate-base and enantiomer relationships. Names include L-malate. Charge state distinguished from the conjugate acid CHEBI:30797.