68123-32-0Relevant academic research and scientific papers
Method for synthesizing benzophenanthridine and protoberberine alkaloids through modular diversity regulation and control
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, (2021/05/29)
The invention discloses a method for synthesizing benzophenanthridine and protoberberine alkaloids through modular diversity regulation and control. The method comprises the following steps: improving a substituent group of a high-iodine salt leaving group, generating pyridine alkyne under the action of relatively mild potassium tert-butoxide, and carrying out [4 + 2] cycloaddition reaction on the pyridine alkyne and diene to obtain polysubstituted isoquinoline ring precursor compounds. Ring opening and aromatization of the isoquinoline ring precursor are realized by developing a novel iridium-catalyzed cross-coupling method, polysubstituted isoquinoline ring compounds with connecting capacity are efficiently synthesized, and then the polysubstituted isoquinoline ring compounds are coupled with a high-activity polysubstituted cyclic boric acid to obtain 3-aryl isoquinoline high-grade intermediates. Through application of two different chemical principles, regulation and control of the 3-aryl isoquinoline high-grade intermediates are realized, and benzophenanthridine and protoberberine alkaloids are modularly, diversely and efficiently synthesized.
Total Synthesis of Khellinone and Khellin. The Pyrogallol Route. Regiospecific Methoxylation of a Benzofuran
Gammill, Ronald B.
, p. 1385 - 1388 (2007/10/02)
Khellinone is prepared in 5 steps from the readily available triacetoxybenzofuran 7.Thr key step in the synthesis is a regiospecific oxidative methoxylation of benzofuran 9.
Anti-atherosclerotic 6,7-dihydro-7,7-disubstituted-khellin analogs
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, (2008/06/13)
The present specification provides novel analogs of khellin. These analogs are all useful as antiatherosclerotic agents. Particularly, the present specification provides 4-methoxy, 9-methoxy, or 4,9-dimethoxy-6,7-dihydro-7,7-disubstituted-5H-furo[3,2-g][1]benzopyran-5-ones.
Pyrogallol synthesis of anti-atherogenic furochromones
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, (2008/06/13)
The present invention provides a total synthesis of known intermediates useful in the synthesis of khellin and antiatherosclerotic analogs thereof from pyrogallol. Pyrogallol is converted to 3,6,7-benzofurantriol triacetate using zinc chloride and chloracetanitrile, then catalytically reduced and deactoxylated at the 3 position to yield the corresponding 2,3-dihydrofuran. This substance is subjected to a Fries rearrangement to the corresponding diol, the phenolic hydroxyl group of which is then selectively alkylated. This yields 6-hydroxy-7-alkoxy-5-benzofuranyl methyl ketone, a known intermediate for the production of 4-desmethoxy khellin and analogs thereof. This compound is then selectively alkoxylated at the 4 position using lead tetraacetate or thallium (III) nitrate in an alkanol solvent to yield known chemical intermediates in the preparation of khellin and analogs thereof.
