6527-13-5Relevant academic research and scientific papers
Synthetic studies towards the penicisulfuranols: Synthesis of an advanced spirocyclic diketopiperazine intermediate
Gayler, Kevin M.,Lambert, Kyle M.,Wood, John L.
, p. 3154 - 3159 (2019/01/29)
The 2,5-diketopiperazine (DKP) moiety is a core feature of many natural products and medicinally relevant scaffolds. As part of our efforts directed towards a total synthesis of penicisulfuranol B, we have developed and report herein: (1) the preparation of an N-hydroxy diketopiperazine intermediate accessible via a molybdenum-mediated oxidation of a parent diketopiperazine, and (2) further synthetic studies leading to a novel spirocyclic dihydrobenzofuran-containing diketopiperazine.
Designing new analogs for streamlining the structure of cytotoxic lamellarin natural products
Tangdenpaisal, Kassrin,Worayuthakarn, Rattana,Karnkla, Supatra,Ploypradith, Poonsakdi,Intachote, Pakamas,Sengsai, Suchada,Saimanee, Busakorn,Ruchirawat, Somsak,Chittchang, Montakarn
, p. 925 - 937 (2015/03/31)
Despite the therapeutic potential of marine-derived lamellarin natural products, their preclinical development has been hampered by their lipophilic nature, causing very poor aqueous solubility. In order to develop more drug-like analogs, their structure was streamlined in this study from both the cytotoxic activity and lipophilicity standpoints. First, a modified total synthetic route was successfully devised to construct a library of 59 systematically designed lamellarin analogs, which were then subjected to cytotoxicity and log P determinations. Along with the 25 first-generation lamellarins previously synthesized in our laboratory, the structure-activity and structure-lipophilicity relationships were extensively evaluated. Our results clearly indicated the additional structural requirements around the lamellarin skeleton which, when combined with those reported previously, can provide invaluable guidance for further modifications to increase the aqueous solubility of these compounds.
Total synthesis of streptonigrone
Chan, Bryan K.,Ciufolini, Marco A.
, p. 8489 - 8495 (2008/02/13)
(Chemical Equation Presented) A total synthesis of streptonigrone, 1, is described, which incorporates a one-step synthesis of substituted pyridones devised in our laboratory. Other aspects of the synthesis that differentiate the present approach from previous ones are the use of a Conrad-Limpach reaction, rather than the customary Friedlaender methodology, to assemble the quinoline segment of 1, and the implementation of an anionic sequence for the functionalization of a key pyridone intermediate.
Total synthesis of natural and unnatural lamellarins with saturated and unsaturated D-rings
Ploypradith, Poonsakdi,Petchmanee, Thaninee,Sahakitpichan, Poolsak,Litvinas, Nichole D.,Ruchirawat, Somsak
, p. 9440 - 9448 (2007/10/03)
(Chemical Equation Presented) Twenty-eight natural and unnatural lamellarins with either a saturated or an unsaturated D-ring were synthesized according to our developed synthetic route. The key step involved the Michael addition/ring closure (Mi-RC) of the benzyldihydroisoquinoline and α-nitrocinnamate derivatives, which provided the 2-carboethoxypyrrole intermediates in moderate to good yields (up to 78% yield). Subsequent hydrogenolysis/lactonization furnished lamellarins with a saturated D-ring in excellent yields (up to 93% yield). DDQ oxidation of the saturated lamellarin acetates led directly to the corresponding unsaturated analogues in 54-95% yield. In addition, only two steps in our developed strategy require column chromatography.
Synthesis and cytotoxic activities of a new benzo[c]phenanthridine alkaloid, 7-hydroxynitidine, and some 9-oxygenated benzo[c]phenanthridine derivatives.
Nakanishi,Suzuki
, p. 985 - 988 (2008/02/09)
[formula: see text] A new benzo[c]phenanthridine alkaloid, 7-hydroxynitidine, was synthesized by a novel synthetic procedure. The cytotoxic activity of this compound against HeLa S3 cells was strong, but not greater than those of its mother compounds, nitidine and NK109. We also synthesized other 9-oxygenated benzo[c]phenanthridine alkaloids, 7-methoxynitidine, 9-demethylnitidine, nitidine, and fagaronine, and tested their cytotoxic activities. These results suggest that the 7-hydroxy group enhances antitumor activity and an 8- or 9-hydroxy group weakens this activity.
Syntheses of the Benzylisoquinoline Alkaloids Isosevanine and Berbithine
Chantimakorn, Vilai,Nimgirawath, Surachai
, p. 209 - 213 (2007/10/02)
The benzylisoquinoline alkaloids isosevanine (1) and berbithine (2) have been synthesized by alkylation of the Reissert compound (5), derived from 6,7-methylenedioxyisoquinoline, with the appropriate benzyl chlorides (6) and (7) respectively followed by hydrogenolysis of the protecting group.
Structure and synthesis of goudotianine, a new 7-methyldehydroaporphine from Guatteria goudotiana
Castedo,Granja,Rodriguez de Lera,Villaverde
, p. 1561 - 1566 (2007/10/02)
Total synthesis of 2,9-dihydroxy-1,3-dimethoxy-7-methyl-6a,7-dehydroaporphine 1a and 3,9-dihydroxy-1,2-dimethoxy-7-methyl-6a,7-dehydroaporphine 1b are described. Direct comparison of both with natural goudotianine isolated from Guatteria goudotiana R.E. Fries showed the latter to be identical with 1b.
Biosynthesis of the isoflavan isomucronulatol: Origin of the 2′,3′,4′-oxygenation pattern
Al-Ani, Hakim A.M.,Dewick, Paul M.
, p. 55 - 61 (2007/10/02)
Feeding experiments with 14C-labelled isoflavones in seedlings and pods of bladder senna (Colutea arborescens) have demonstrated that 7-hydroxy-4′-methoxyisoflavone (formononetin), 7,3′-dihydroxy-4′-methoxyisoflavone (calycosin), 7,2′,3′-trihydroxy-4′-methoxyisoflavone (koparin) and 7,2′-dihydroxy-3′,4′-dimethoxyisoflavone are excellent precursors of (3R)-isomucronulatol (7,2′-dihydroxy-3′,4′-dimethoxyisoflavan). 7,2′-Dihydroxy- 4′-methoxyisoflavone (2′-hydroxyformononetin) and 7-hydroxy-3′,4′-dimethoxyisoflavone (cladrin) were, however, poor substrates. Thus, the biosynthetic sequence to isomucronulatol from formononetin involves 3′-hydroxylation, 2′-hydroxylation and then 3′-O-methylation, followed presumably by stereospecific reduction of 7,2′-dihydroxy-3′,4′-dimethoxyisoflavone. Treatment of 2′,3′,4′-trimethoxyisoflavones with aluminium chloride in acetonitrile gives modest yields of 2′,3′-dihydroxy derivatives rather than 2′-monohydroxyisoflavones, and thus provides a convenient access to 2′,3′-dihydroxyisoflavones and related pterocarpans.
SYNTHESIS OF NATURAL ISOFLAVANQUINONES BY THE OXIDATIVE REARRANGEMENT OF CHALCONES WITH THALLIUM(III) NITRATE: ABRUQUINONES A AND B
Lupi, Alessandro,Marta, Maurizio,Lintas, Graziella,Marini Bettolo, Giovanni Battista
, p. 625 - 628 (2007/10/02)
The natural isoflavanquinones abruquinone A and B have been synthesized through the oxidative rearrangement of chalcones with Tl(NO3)3.The previously proposed structures are confirmed.
