Of alkaloid-like compounds

Combinatorial Synthesis of Alkaloid-like Compounds In Search of Chemical Probes of Protein-Protein Interactions... 

In the field of the components of the venom from toads, he studied the venom of most South American species of the genus Bufo, determining with several coworkers, and also in collaboration with T. Reichstein (University of Basel), their composition in regard to bufadienolides, bioge-netic amines, and alkaloid-like compounds. 

An alkaloid-like compound, GPA-1734, described as 8,9-dihydroxy-7-methylbenzo[ ]quinolizinium bromide [117] (probable structure, (42)) was reported to inhibit a partially purified calf lens AR and to have an IC50 value of 1 x 10" 5 to 7 x 10 6 M [117]. No in vivo results were reported. 

Diterpenic acid-based alkaloid-like compounds as new group of nootropic agents 01MI97. 

Cuzin, J.L. Liber einige AUcaloidahnliche Verbindungen des Tabakrauches [About several alkaloid-like compounds of tobacco smoke] Abhandl. Dev. Akad. Berlin Klin. Chem. Geol. Biol. (1966) 171-172, 181-186. 

A number of examples such as 1,3-dioxanes, macrolactones, °° ring-containing biaryls, ° spirooxindoles, alkaloid-like compounds, and polycyclic compounds from the Schreiber group illustrate this approach to natural product-like libraries (see Chapter 11). An early example converted shikimic acid into intermediate tetracyclic y-butyrolactones, which were then functionalized around the core structure (see Chapter 11, Subsection 11.10.2). y-Butyrolactones, found in about 10% of all natural products and which exhibit a broad range of biological activities, are a key element in a number of recent natural product-like compounds. A more recent example, inspired by the rich skeletal diversity of indole alkaloids, utilized the rhodium(II)-catalyzed consecutive cyclization-cycloaddition reactions developed by Padwa and coworkers (Scheme 1.4). A stereocontrolled tandem reaction utilizing the versatile scaffold allowed for multiple modes of intramolecular reactions. 

Woodhead and Swain (1974), who investigated the biosynthesis of the alkaloid-like compound amaranthine encountered in Chenopodiaceae, have demonstrated the effect of light on the rate of biosynthesis of this pigment. The authors believe that the synthesis is controlled by phytochrome with a probable involvement at a higher level of light (Figure 3.5). 

Reserpine (Fig. 4), an alkaloid extracted from Rauwolfia serpentina, and many other natural or synthetic substances block the storage of monoamines (catecholamines as well as 5-HT) the resulting depletion of the amine stores is accompanied by a rise of acidic metabolites in the urine. This property of reserpine-like compounds to deplete monoamines stores has great experimental and clinical value... 

The latter is the source of the Chinese dmg Chin-Shih-Hu. Compared to the other families of bases discussed eadier, the numbers of alkaloids supposedly derived from famesyl pyrophosphate or a close relative is small. However, given the wide variety of plant families containing sesquiterpenes, it is most likely that the numbers of compounds to be found will dramatically increase. 

The intramolecular Pummerer reaction has been applied to the synthesis of simple quinolizidine alkaloids like lupinine <2000JOC2368>, and also to arenoquinolizine alkaloids. Thus, the 2-(2-piperidyl)indole 284 was converted to indolo[2,3- ]quinolizidine 287 following a protocol that has as the key step the regioselective cyclization onto the indole 3-position of a thionium ion generated by Pummerer reaction from the appropriately substituted compound... 

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