Structural determination of four manufacturing impurities of D&C Red No. 33.

Four manufacturing impurities of D&C Red No. 33 isolated by counter-current chromatography were analyzed by NMR and ESI mass spectrometry. Three of these impurities were reported previously with minimal details of structural determination.

Perseorangin: A natural pigment from avocado (Persea americana) seed.

High consumer demand has led global food color manufacturers and food companies to dramatically increase the development and use of natural colors. We have previously reported that avocado (Persea americana) seeds, when crushed in the presence of air, develop a red-orange color in a polyphenol oxidase-dependent reaction. The objective of this study was to identify the major colored compound in colored avocado seed extract (CASE).

The role of computer-assisted structure elucidation (CASE) programs in the structure elucidation of complex natural products.

Covering: up to the end of December, 2018 There are still a disturbing number of incorrect natural product structure elucidations reported in the literature. The use of Computer-Assisted Structure Elucidation (CASE) programs can minimize this risk by generating all structures that are consistent with the input data and by ranking these structures in order of probability. They can successfully determine structures for complex natural products, with the possible exception of compounds with very few protons.

Elucidation and partial NMR assignment of monosulfated maitotoxins from the Caribbean.

Compounds similar to maitotoxin (MTX) have been isolated from several laboratory strains of the dinoflagellate Gambierdiscus spp. from the Caribbean. Mass spectral results suggest that these compounds differ from MTX by the loss of one sulfate group and, in some cases, the loss of one methyl group with the addition of one degree of unsaturation.

Identification of 1',5'-naphthyridinophthalone and its quantification in the color additive D&C Yellow No. 10 (Quinoline Yellow) using high-performance liquid chromatography.

The present work reports the identification and characterization of a contaminant, 2-(2'-(1,5-naphthyridinyl))-1,3-indanedione (1',5'-naphthyridinophthalone, 1,5NP), in the color additive D&C Yellow No. 10 (U.S.

Profiling hydroxycinnamic acid glycosides, iridoid glycosides, and phenylethanoid glycosides in baobab fruit pulp (Adansonia digitata).

The baobab (Adansonia digitata L.) is a magnificent tree revered throughout Africa and is becoming recognized for its high nutritional and medicinal values. Despite numerous reports on the pharmacological potential, little is known about its chemical compositions.

Application of a computer-assisted structure elucidation program for the structural determination of a new terpenoid aldehyde with an unusual skeleton.

The structure of a novel compound from Adansonia digitata has been elucidated, and its H and C NMR spectra have been assigned employing a variety of one-dimensional and two-dimensional NMR techniques without degradative chemistry. The Advanced Chemistry Development ACD/Structure Elucidator software was important for determining part of this structure that contained a fused bicyclic system with very few hydrogen atoms, which in turn, exhibited essentially no discriminating HMBC connectivities throughout that portion of the molecule. Copyright © 2016 John Wiley & Sons, Ltd.

Preparative separation and identification of novel subsidiary colors of the color additive D&C Red No. 33 (Acid Red 33) using spiral high-speed counter-current chromatography.

Three low-level subsidiary color impurities (A, B, and C) often present in batches of the color additive D&C Red No. 33 (R33, Acid Red 33, Colour Index No. 17200) were separated from a portion of R33 by spiral high-speed counter-current chromatography (HSCCC).

Sesquiterpenoid tropolone glycosides from Liriosma ovata.

Two new sesquiterpenoid tropolone glycosides, liriosmasides A (1) and B (2), along with two known compounds, secoxyloganin and oplopanpheside C, were isolated from a methanol extract of the roots of Liriosma ovata. The structures of 1 and 2 were elucidated by spectroscopic methods including 1D and 2D NMR and by high-resolution mass spectrometry involving an ultra-high-performance liquid chromatography-quadrupole-orbital ion trap mass spectrometric (UHPLC-Q-Orbitrap MS) method. Compound 1 showed weak inhibitory activity against HIV RNase H.

Preparative separation of two subsidiary colors of FD&C Yellow No. 5 (Tartrazine) using spiral high-speed counter-current chromatography.

Specifications in the U.S. Code of Federal Regulations for the color additive FD&C Yellow No.

Analysis of processing contaminants in edible oils. Part 1. Liquid chromatography-tandem mass spectrometry method for the direct detection of 3-monochloropropanediol monoesters and glycidyl esters.

A new analytical method has been developed and validated for the detection of glycidyl esters (GEs) and 3-monochloropropanediol (3-MCPD) monoesters in edible oils. The target compounds represent two classes of potentially carcinogenic chemical contaminants formed during the processing of edible oils. Target analytes are separated from edible oil matrices using a two-step solid-phase extraction (SPE) procedure.

Preparation of two novel monobrominated 2-(2',4'-dihydroxybenzoyl)-3,4,5,6-tetrachlorobenzoic acids and their separation from crude synthetic mixtures using vortex counter-current chromatography.

The present work describes the preparation of two compounds considered to be likely precursors of an impurity present in samples of the color additives D&C Red No. 27 (Color Index 45410:1) and D&C Red No. 28 (Color Index 45410, phloxine B) submitted to the U.

Preparative separation of 1,3,6-pyrenetrisulfonic acid trisodium salt from the color additive D&C Green No. 8 (pyranine) by pH-zone-refining counter-current chromatography.

In developing analytical methods for batch certification of the color additive D&C Green No. 8 (G8), the U.S.

Accurate mass and nuclear magnetic resonance identification of bisphenolic can coating migrants and their interference with liquid chromatography/tandem mass spectrometric analysis of bisphenol A.

Two unknown compounds were previously determined to be potential interferences in liquid chromatography/tandem mass spectrometry (LC/MS/MS) analysis of bisphenol A (BPA) in canned infant formula. Both yielded two identical MS/MS transitions to BPA. The identities of the unknowns were investigated using accurate mass LC/MS, LC/MS/MS, and elemental formula and structures proposed.

Utility of coupled-HSQC experiments in the intact structural elucidation of three complex saponins from Blighia sapida.

The structures of three complex saponins from the fruit pods of Blighia sapida have been elucidated and their (1)H and (13)C NMR spectra assigned employing a variety of one- and two-dimensional NMR techniques without degradative chemistry. The saponins have either four or six monosaccharide units linked to a triterpene aglycone. High-resolution, proton-coupled-HSQC spectra were important for determining both the identities of the intact monosaccharide units and coupling constants in strongly coupled proton spin systems.

Trapping a labile adduct formed between an ortho-quinone methide and 2'-deoxycytidine.

Selective oxidation by bis[(trifluoroacetoxy)iodo]benzene (BTI) provides an effective trap for quenching adducts formed reversibly between dC and an ortho-quinone methide (QM) under physiological conditions. A model adduct generated by 4-methyl-o-QM and 2'-deoxycytidine is rapidly converted by intramolecular cyclization and loss of aromaticity to a characteristic product for quantifying QM alkylation. However, BTI induces a surprising rearrangement driven by overoxidation of a derivative lacking an alkyl substituent at the 4-position of the QM.

Cucurbitane-type triterpenoids from Momordica charantia.

One new cucurbitane-type triterpenoid glycoside, momordicoside U (1), together with five known cucurbitane-type triterpenoids and related glycosides, 3β,7 β,25-trihydroxycucurbita-5,23 (E)-dien-19-al (2), momordicine I (3), momordicine II (4), 3-hydroxycucurbita-5,24-dien-19-al-7,23-di-O-β-glucopyranoside (5), and kuguaglycoside G (6), were isolated from the whole plant of Momordica charantia. Their structures were determined by chemical and spectroscopic methods. Momordicoside U (1) was evaluated for insulin secretion activity in an in vitro insulin secretion assay and displayed moderate activity.

Chiral stationary phases for separation of intermedine and lycopsamine enantiomers from Symphytum uplandicum.

Enantioseparation of the pyrrolizidine alkaloid isomers intermedine and lycopsamine, isolated from Symphytum uplandicum, is discussed. The separatory power of two immobilized carbohydrate-based chiral HPLC columns, Chiralpak IA and IC, in different chromatographic conditions is compared. The study demonstrated the importance of solvent and column selection while developing such chiral HPLC separation methods.

Preparative separation of di- and trisulfonated components of Quinoline Yellow using affinity-ligand pH-zone-refining counter-current chromatography.

Four positionally isomeric 2-(2-quinolinyl)-1H-indene-1,3(2H)-dionedisulfonic acids (SA) and one triSA, components of the color additive Quinoline Yellow (QY, Color Index No. 47005), were isolated from the dye mixture by affinity-ligand pH-zone-refining counter-current chromatography (CCC) through complementary use of ion-exchange and ion-pair reagents as the ligand. The added ligands facilitated the partitioning of the very polar polysulfonated components into the organic stationary phase of the two-phase solvent systems that consisted of isoamyl alcohol-methyl tert-butyl ether-acetonitrile-water (3:5:1:7), (3:4:1:7) or (3:1:1:5).

Alkaloids and saponins in dietary supplements of blue cohosh (Caulophyllum thalictroides).

Preparations of blue cohosh (Caulophyllum thalictroides) have been used traditionally by Native Americans for medicinal purposes. Dietary supplements containing dried roots or extracts of blue cohosh rhizomes are available as dietary supplements. The safety and efficacy of these preparations have not been systematically evaluated.

Partial synthesis of (3R,6'R)-alpha-cryptoxanthin and (3R)-beta-cryptoxanthin from (3R,3'R,6'R)-lutein.

(3R,3'R,6'R)-Lutein (1), (3R,3'R)-zeaxanthin (2), (3R,6'R)-alpha-cryptoxanthin (3), and (3R)-beta-cryptoxanthin (4) are among dietary hydroxycarotenoids that have been identified in human serum, milk, and ocular tissues. While 1 containing 6% of 2 is commercially available, industrial production of optically active 3 and 4 has not yet been accomplished. Several processes have been developed that transform 1 into 3, 4, and minor quantities of (3R,5'RS,6'R)-3',4'-didehydro-5',6'-dihydro-beta,beta-caroten-3-ol (5) (a regioisomer of 3).