List of works - John Brent Friesen

An experimental implementation of chemical subtraction.

scientific article published on 17 December 2007

Analysis and purification of bioactive natural products: the AnaPurNa study.

scientific article

Can Invalid Bioactives Undermine Natural Product-Based Drug Discovery?

scientific article

Correction to Importance of Purity Evaluation and the Potential of Quantitative (1)H NMR as a Purity Assay

scientific article published on 17 November 2015

Countercurrent Separation of Natural Products: An Update

scientific article

Countercurrent assisted quantitative recovery of metabolites from plant-associated natural deep eutectic solvents

scientific article

Countercurrent separation assisted identification of two mammalian steroid hormones in Vitex negundo

scientific article published on 21 April 2018

Countercurrent separation of natural products.

scientific article published on 31 July 2008

Design of countercurrent separation of Ginkgo biloba terpene lactones by nuclear magnetic resonance

scientific article (publication date: 15 June 2012)

Dissemination of original NMR data enhances reproducibility and integrity in chemical research

scientific article

Dynamics of the isoflavone metabolome of traditional preparations of Trifolium pratense L

scientific article published on 11 April 2019

Elution-extrusion countercurrent chromatography: theory and concepts in metabolic analysis

scientific article published on 5 April 2007

HiFSA fingerprinting applied to isomers with near-identical NMR spectra: the silybin/isosilybin case

scientific article published on 5 March 2013

Importance of purity evaluation and the potential of quantitative ¹H NMR as a purity assay.

scientific article

Isolation and Pharmacological Characterization of Six Opioidergic Picralima nitida Alkaloids

scientific article published on 16 December 2020

K-targeted metabolomic analysis extends chemical subtraction to DESIGNER extracts: selective depletion of extracts of hops (Humulus lupulus).

scientific article published on December 2014

Linear regression analysis of silychristin A, silybin A and silybin B contents in Silybum marianum

scientific article published on 29 November 2018

Natural Deep Eutectic Solvents: Properties, Applications, and Perspectives.

scientific article published on 7 March 2018

Occurrence of progesterone and related animal steroids in two higher plants.

scientific article

Orthogonal Analysis Underscores the Relevance of Primary and Secondary Metabolites in Licorice.

scientific article published on 31 July 2014

Performance characteristics of countercurrent separation in analysis of natural products of agricultural significance.

scientific article

Phytoconstituents from Vitex agnus-castus fruits ⬇️

scientific article

Preparation of DESIGNER extracts of red clover (Trifolium pratense L.) by centrifugal partition chromatography

scientific article published on 29 May 2019

Preparation of flavone di-C-glycoside isomers from Jian-Gu injection (Premna fulva Craib.) using recycling counter-current chromatography

scientific article published on 21 March 2019

Qualitative and quantitative evaluation of solvent systems for countercurrent separation

scientific article published on 04 December 2014

Quantification of a botanical negative marker without an identical standard: ginkgotoxin in Ginkgo biloba.

scientific article published on 16 January 2014

Quantum Mechanics-Based Structure Analysis of Cyclic Monoterpene Glycosides from Rhodiola rosea

scientific article published on 28 May 2020

Rational development of solvent system families in counter-current chromatography

scientific article published on 04 February 2007

Real-Time Volumetric Phase Monitoring: Advancing Chemical Analysis by Countercurrent Separation

scientific article

Reciprocal symmetry plots as a representation of countercurrent chromatograms

scientific article published on 14 February 2007

Selective Chlorophyll Removal Method to "Degreen" Botanical Extracts

scientific article published on 19 May 2020

Selective Depletion and Enrichment of Constituents in "Curcumin" and Other Curcuma longa Preparations

scientific article published on 08 March 2019

Selective Preparation and High Dynamic-Range Analysis of Cannabinoids in “CBD Oil” and Other Cannabis sativa Preparations

scientific article published in 2022

Separation of natural products by countercurrent chromatography

scientific article published on 01 January 2012

Silica Gel-mediated Oxidation of Prenyl Motifs Generates Natural Product-Like Artifacts

scientific article published in 2021

Silybum marianum pericarp yields enhanced silymarin products.

scientific article

Solvent System Selection Strategies in Countercurrent Separation

scientific article

Studying Mass Balance and the Stability of (Z)-Ligustilide from Angelica sinensis Helps to Bridge a Botanical Instability-Bioactivity Chasm

scientific article published on 03 September 2019

Sweet spot matching: A thin-layer chromatography-based countercurrent solvent system selection strategy

scientific article published on 27 April 2017

Tandem of Countercurrent Separation and qHNMR Enables Gravimetric Analyses: Absolute Quantitation of the Rhodiola rosea Metabolome

scientific article published in 2021

The 9th International Countercurrent Chromatography Conference held at Dominican University, Chicago, USA, August 1-3, 2016.

scientific article published on 19 September 2017

The Generally Useful Estimate of Solvent Systems (GUESS) method enables the rapid purification of methylpyridoxine regioisomers by countercurrent chromatography.

scientific article

The Untargeted Capability of NMR Helps Recognizing Nefarious Adulteration in Natural Products

scientific article published on 12 March 2021

The influence of natural deep eutectic solvents on bioactive natural products: studying interactions between a hydrogel model and Schisandra chinensis metabolites.

scientific article published on 21 February 2018

Toward Structural Correctness: Aquatolide and the Importance of 1D Proton NMR FID Archiving

scientific article

List of works by John Brent Friesen

An experimental implementation of chemical subtraction.

Analysis and purification of bioactive natural products: the AnaPurNa study.

Can Invalid Bioactives Undermine Natural Product-Based Drug Discovery?

Correction to Importance of Purity Evaluation and the Potential of Quantitative (1)H NMR as a Purity Assay

Countercurrent Separation of Natural Products: An Update

Countercurrent assisted quantitative recovery of metabolites from plant-associated natural deep eutectic solvents

Countercurrent separation assisted identification of two mammalian steroid hormones in Vitex negundo

Countercurrent separation of natural products.

Design of countercurrent separation of Ginkgo biloba terpene lactones by nuclear magnetic resonance

Dissemination of original NMR data enhances reproducibility and integrity in chemical research

Dynamics of the isoflavone metabolome of traditional preparations of Trifolium pratense L

Elution-extrusion countercurrent chromatography: theory and concepts in metabolic analysis

HiFSA fingerprinting applied to isomers with near-identical NMR spectra: the silybin/isosilybin case

Importance of purity evaluation and the potential of quantitative ¹H NMR as a purity assay.

Isolation and Pharmacological Characterization of Six Opioidergic Picralima nitida Alkaloids

K-targeted metabolomic analysis extends chemical subtraction to DESIGNER extracts: selective depletion of extracts of hops (Humulus lupulus).

Linear regression analysis of silychristin A, silybin A and silybin B contents in Silybum marianum

Natural Deep Eutectic Solvents: Properties, Applications, and Perspectives.

Occurrence of progesterone and related animal steroids in two higher plants.

Orthogonal Analysis Underscores the Relevance of Primary and Secondary Metabolites in Licorice.

Performance characteristics of countercurrent separation in analysis of natural products of agricultural significance.

Phytoconstituents from Vitex agnus-castus fruits ⬇️

Preparation of DESIGNER extracts of red clover (Trifolium pratense L.) by centrifugal partition chromatography

Preparation of flavone di-C-glycoside isomers from Jian-Gu injection (Premna fulva Craib.) using recycling counter-current chromatography

Qualitative and quantitative evaluation of solvent systems for countercurrent separation

Quantification of a botanical negative marker without an identical standard: ginkgotoxin in Ginkgo biloba.

Quantum Mechanics-Based Structure Analysis of Cyclic Monoterpene Glycosides from Rhodiola rosea

Rational development of solvent system families in counter-current chromatography

Real-Time Volumetric Phase Monitoring: Advancing Chemical Analysis by Countercurrent Separation

Reciprocal symmetry plots as a representation of countercurrent chromatograms

Selective Chlorophyll Removal Method to "Degreen" Botanical Extracts

Selective Depletion and Enrichment of Constituents in "Curcumin" and Other Curcuma longa Preparations

Selective Preparation and High Dynamic-Range Analysis of Cannabinoids in “CBD Oil” and Other Cannabis sativa Preparations

Separation of natural products by countercurrent chromatography

Silica Gel-mediated Oxidation of Prenyl Motifs Generates Natural Product-Like Artifacts

Silybum marianum pericarp yields enhanced silymarin products.

Solvent System Selection Strategies in Countercurrent Separation

Studying Mass Balance and the Stability of (Z)-Ligustilide from Angelica sinensis Helps to Bridge a Botanical Instability-Bioactivity Chasm

Sweet spot matching: A thin-layer chromatography-based countercurrent solvent system selection strategy

Tandem of Countercurrent Separation and qHNMR Enables Gravimetric Analyses: Absolute Quantitation of the Rhodiola rosea Metabolome

The 9th International Countercurrent Chromatography Conference held at Dominican University, Chicago, USA, August 1-3, 2016.

The Generally Useful Estimate of Solvent Systems (GUESS) method enables the rapid purification of methylpyridoxine regioisomers by countercurrent chromatography.

The Untargeted Capability of NMR Helps Recognizing Nefarious Adulteration in Natural Products

The influence of natural deep eutectic solvents on bioactive natural products: studying interactions between a hydrogel model and Schisandra chinensis metabolites.

Toward Structural Correctness: Aquatolide and the Importance of 1D Proton NMR FID Archiving