Quinine chemical structure

FIG. 22 Chemical structures of (a) dextromethorphan hydrobromide, (b) papaverine hydrochloride, (c) quinine hydrochloride, and (d) berberine chloride. 

Fig. 16 Chemical structures of quinine and mefloquine, and their ferrocenyl conjugates. The hypothetical carbenium is presented on the right...

A first requirement for a substance to produce a taste is that it be water soluble. The relationship between the chemical structure of a compound and its taste is more easily established than that between structure and smell. In general, all acid substances are sour. Sodium chloride and other salts are salty, but as constituent atoms get bigger, a bitter taste develops. Potassium bromide is both salty and bitter, and potassium iodide is predominantly bitter. Sweetness is a property of sugars and related compounds but also of lead acetate, beryllium salts, and many other substances such as the artificial sweeteners saccharin and cyclamate. Bitterness is exhibited by alkaloids such as quinine, picric acid, and heavy metal salts. 

Fig. 7.22 (A) Chemical structures of the quinine and quinidine tert-butylcarbamate-based CHIRALPAK QN-AX and CHIRALPAK QD-AX anion exchange-type CSPs. These CSPs show pseudo-enantiomeric chiral recognition pro-...

The traditional method of drag development, at least in this century, has been to develop leads by first using, and then by isolating and identifying, the active chemical constituents from natural products, some of which may have been medicinally in use since antiquity. With the advent of modem organic chemistry some of these purified compounds were used directly (e.g., morphine, cocaine, atropine, quinine), and, once their chemical structures were ascertained, they became leads for hoped-for chemical modifications to achieve improved efficacy, less toxicity, or, at least, higher potency (e.g., dihydromorphinone, homatropine, acetylsalicylic acid). 

Fig. 9.12 Chemical structures of drugs used for the treatment of PD, ALS, and HD in animal models. Pyrroloquinoline quinine (a) riluzole (b) minocycline (c) and coenzyme Qio (d)...

Other Names Cinchoninic acid, 6-methoxy- 6-Methoxy-4-quinolinecarboxylic acid 6-Methoxy-cinchoninic acid NSC 403610 Quininic acid CA Index Name 4-Quinolinecarboxylic acid, 6-methoxy-CAS Registry Number 86-68-0 Merck Index Number 8062 Chemical Structure... 

Flg. 1. Chemical structures of quinine and quinidine. The chiral C atom is indicated with an arrow (modified from Bircher 1996)... 

Fig. 9 Chemical structure of tetrathiafulvalene left) and quinine right)...

Fig. 6 Chemical structure of quinine (QN)- and quinidine (QD)-CSs used in ref. [64]. The structural modifications introduced on the alkaloids structure and the recognition model described for DNB-( )-Leu are indicated...

They were neutralised with quinine, nicotine, tartaric acid, mandelic acid or (+)-camphor-sulfonic acid. Naturally the optical rotation is changed by the salt formation, but it turns out that the optical rotation of a polymer salt (measured in DMF or methanol) does not depend only on the chemical structure, but also on the tacticity. For example, the optical rotation of the quinine salt of isotactic polystyrenesulfonic acid is considerably more negative than that of the atactic polymer. The tartrates of isotactic poly-2-vinylpyridine are more strongly dextrorotatory than the atactic ones. The optical rotation of the nicotine salts of isotactic and atactic polymethacrylic acid also differs greatly [83]. Finally, mention should be made of complex formation between polymers and chiral shift reagents. Since however the NMR signals and not the CD are investigated in such reactions, they are outside the scope of this report. 

At the time, little was known about the internal structure of compounds or about how one compound was transformed into another. Chemists concentrated instead on the proportions of various chemicals in a substance. Hofmann realized that the proportions of ingredients in the antimalaria drug quinine— 20 equivalents of carbon, 11 equivalents of hydrogen, 1 equivalent of nitrogen, and 2 equivalents of oxygen —were almost identical to those in aniline. The difference was only two equivalents of water. Hofmann speculated that he might be able to turn aniline into quinine. With European colonization headed toward the tropics, the drug was desperately needed. 

Although far less numerous than the terpenoid/isoprenoid or polyketide NPs, the alkaloids (with an estimated 20,000 different structures) have a special place in NP research because a few are of great value to humans—for example, morphine, theobromine, caffeine, vincristine, quinine, codeine, cocaine, nicotine and strychnine. These often complex chemicals are found in about 20% of vascular plants and a smaller number of fungi, marine invertebrates and a few bacteria. ... 

---