Related Experiment Video

Updated: Jun 14, 2026

A Direct, Early Stage Guanidinylation Protocol for the Synthesis of Complex Aminoguanidine-containing Natural Products
09:04

A Direct, Early Stage Guanidinylation Protocol for the Synthesis of Complex Aminoguanidine-containing Natural Products

Published on: September 9, 2016

Conversion of hydroquinidine into hydrocinchonine and of cupreine into cinchonidine

H KING

    Journal of the Chemical Society
    |March 19, 2010
    PubMed
    Abstract

    No abstract available in PubMed .

    Keywords:
    CINCHONIDINE

    More Related Videos

    Facile Preparation of 4-Substituted Quinazoline Derivatives11:51

    Facile Preparation of 4-Substituted Quinazoline Derivatives

    Published on: February 15, 2016

    Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions07:12

    Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions

    Published on: July 17, 2020

    Related Concept Videos

    Cholinergic Antagonists: Pharmacokinetics01:24

    Cholinergic Antagonists: Pharmacokinetics

    Cholinergic antagonists—such as antimuscarinics—are available in oral, topical, ocular, parenteral, and inhalational formulations. Most antimuscarinics are oral formulations,  while scopolamine is available as a topical patch, and ipratropium and tiotropium are available as inhalation aerosols or powders. Atropine, tropicamide, and cyclopentolate are topically instilled in the eye. Most antimuscarinics are lipid-soluble and readily absorbed from the gastrointestinal tract and the conjunctiva.
    Phase II Reactions: Miscellaneous Conjugation Reactions01:19

    Phase II Reactions: Miscellaneous Conjugation Reactions

    Phase II biotransformations are detoxification mechanisms that conjugate xenobiotics with endogenous substances, neutralizing their toxicity.
    A key example involves the conjugation of cyanide ions, which impair cellular respiration and alter hemoglobin into non-oxygen-carrying cyanmethemoglobin. To neutralize this threat, a sulfur atom from thiosulphate is transferred to the cyanide ion, catalyzed by the enzyme rhodanese, resulting in an inactive compound called thiocyanate. The production of...
    Direct-Acting Cholinergic Agonists: Pharmacokinetics01:31

    Direct-Acting Cholinergic Agonists: Pharmacokinetics

    Direct-acting cholinergic agonists, such as synthetic choline esters and naturally occurring alkaloids, exert their effects by enhancing the actions of acetylcholine and stimulating the parasympathetic nervous system. Synthetic choline esters share structural similarities with acetylcholine. For example, they have a positively charged quaternary ammonium or onium group, contributing to their hydrophilic characteristics. As a result, they are poorly absorbed in the body through oral...
    Aldehydes and Ketones with HCN: Cyanohydrin Formation Overview01:32

    Aldehydes and Ketones with HCN: Cyanohydrin Formation Overview

    Cyanohydrins are compounds that contain –CN and –OH groups on the same carbon atom. They are formed by the nucleophilic addition of the cyanide ions to the carbonyl group. Cyanide ions are highly basic and nucleophilic and can be generated from HCN under aqueous conditions. However, since HCN is a weak acid, the number of cyanide ions generated is very small. Hence, a small amount of base or KCN/NaCN is added to HCN to increase the concentration of the cyanide ions in the reaction mixture.
    Preparation of 1° Amines: Hofmann and Curtius Rearrangement Overview01:07

    Preparation of 1° Amines: Hofmann and Curtius Rearrangement Overview

    In the presence of an aqueous base and a halogen, primary amides can lose the carbonyl (as carbon dioxide) and undergo rearrangement to form primary amines. This reaction, called the Hofmann rearrangement, can produce primary amines (aryl and alkyl) in high yields without contamination by secondary and tertiary amines.
    Oxidation of Phenols to Quinones01:17

    Oxidation of Phenols to Quinones

    In the presence of oxidizing agents, phenols are oxidized to quinones. Quinones can be easily reduced back to phenols using mild reducing agents. The electron-donating hydroxyl group enhances the reactivity of the aromatic ring, enabling oxidation of the ring even in the absence of an α hydrogen.
    o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox property is crucial in...