38996-01-9Relevant articles and documents
Double diastereoselection in intramolecular photocycloadditions: A radical rearrangement approach to the total synthesis of the spirovetivane phytoalexin (±)-lubiminol
Crimmins, Michael T.,Wang, Zhuo,McKerlie, Lynne A.
, p. 1747 - 1756 (1998)
The highly stereoselective total synthesis of the phytoalexin (±)-lubiminol (1) has been accomplished. The synthesis relies on three pivotal transformations: (1) a conjugate addition-cyclization reaction to prepare a highly functionalized 2-carbomethoxycyclopentenone as a photocycloaddition substrate, (2) a double diastereoselective intramolecular photocycloaddition for a stereoselective intramolecular photoaddition reaction which establishes the central quaternary spirocenter, and (3) the transformation of the photoadduct into the required spiro[5.4]decane through a radical fragmentation-rearrrangement reaction.
2,3-cis-Cyclization of 4-pentenoxyl radicals
Kempter, Irina,Schur, Christine,Huttenlochner, Katharina,Bergstr??er, Ruth-Maria,Wolff, Benjamin,Kopf, Thomas,Hartung, Jens
, p. 7699 - 7714 (2016)
4-Pentenoxyl radicals cyclize 2,3-cis-selectively, when substituted by an allylic hydroxy, acetyloxy, or benzoyloxy group. Additional substituents increase or decrease the fraction of 2,3-cis-cyclized product, depending on relative configuration, position
Rearrangement of cyclobutyl carbinyl radicals: Total synthesis of the spirovetivane phytoalexin (±)-lubiminol
Crimmins, Michael T.,Wang, Zhuo,McKerlie, Lynne A.
, p. 8703 - 8706 (1996)
The total synthesis of the phytoalexin (±)-lubiminol 1 has been accomplished. The synthesis relies on a conjugate addition-cyclization reaction to prepare a photosubstrate for a stereoselective intramolecular photoaddition reaction. The photoadduct is and formed into the required spiro [5.4] decane through a radical fragmentation-rearrangement reaction.
Total Synthesis of an Isatis indigotica-Derived Alkaloid Using a Biomimetic Thio-Diels-Alder Reaction
Davison, Emma K.,Hume, Paul A.,Sperry, Jonathan
, p. 3545 - 3548 (2018)
A biomimetic thio-Diels-Alder reaction between a dienylthiadiazole and 3-thioisatin leads to the Isatis indigotica-derived alkaloid (1), along with its diastereomer 2. This synthetic study, supported by molecular modeling, establishes the viability of the proposed biosynthesis by thio-Diels-Alder cycloaddition, a very rare reaction in nature. Moreover, the results described infer that the diastereomer 2 is an as-yet undiscovered natural product present in Isatis indigotica.
Total synthesis of PGF2α and 6,15-diketo-PGF1α and formal synthesis of 6-keto-PGF1α via three-component coupling
Kim, Taehyeong,Lee, Sung Il,Kim, Sejin,Shim, Su Yong,Ryu, Do Hyun
supporting information, (2019/09/17)
The asymmetric total synthesis of PGF2α and 6,15-diketo-PGF1α and formal synthesis of 6-keto-PGF1α from a common key intermediate are described. The key intermediate, which has a chiral cyclopentane backbone possessing suitable functional groups with required stereochemistry for both side chains, was prepared from (R)-4-silyloxy-2-cyclopentenone through a three-component coupling reaction. The Wittig reaction, Nozaki-Hiyama-Kishi (NHK) coupling and cross metathesis completed the synthesis of PGF2α, 6,15-diketo-PGF1α and 6-keto-PGF1α.
Continuous Pd-Catalyzed Carbonylative Cyclization Using Iron Pentacarbonyl as a CO Source
Lopatka, Pavol,Markovi?, Martin,Koó?, Peter,Ley, Steven V.,Gracza, Tibor
, p. 14394 - 14406 (2019/11/11)
This work discloses a continuous flow carbonylation reaction using iron pentacarbonyl as source of CO. The described transformation using this surrogate was designed for use in commonly accessible flow equipment. Optimized conditions were applied to a sca
Rhodium-Catalyzed Cyclization of O,ω-Unsaturated Alkoxyamines: Formation of Oxygen-Containing Heterocycles
Escudero, Julien,Bellosta, Véronique,Cossy, Janine
supporting information, p. 574 - 578 (2018/02/21)
O,ω-Unsaturated N-tosyl alkoxyamines undergo unexpected RhIII-catalyzed intramolecular cyclization by oxyamination to produce oxygen-containing heterocycles. Mechanistic studies show that an aziridine intermediate seems to be responsible for the formation of the heterocycles, possibly via a RhV species.
Scalable synthesis enabling multilevel bio-evaluations of natural products for discovery of lead compounds
Zhu, Lizhi,Ma, Wenjing,Zhang, Mengxun,Lee, Magnolia Muk-Lan,Wong, Wing-Yan,Chan, Brandon Dow,Yang, Qianqian,Wong, Wing-Tak,Tai, William Chi-Shing,Lee, Chi-Sing
, (2018/04/05)
Challenges in the development of anti-cancer chemotherapeutics continue to exist, particularly with respect to adverse effects and development of resistance, underlining the need for novel drugs with good safety profiles. Natural products have proven to be a fertile ground for exploitation, and development of anti-cancer drugs from structurally complex natural products holds promise. Unfortunately, this approach is often hindered by low isolation yields and limited information from preliminary cell-based assays. Here we report a concise and scalable synthesis of a series of low-Abundance Isodon diterpenoids (a large class of natural products with over 1000 members isolated from the herbs of genus Isodon, which are well-known folk medicines for the treatment of inflammation and cancer), including eriocalyxin B, neolaxiflorin L and xerophilusin I. These scalable syntheses enable multilevel bio-evaluation of the natural products, in which we identify neolaxiflorin L as a promising anti-cancer drug candidate.
Rhodium Carbenoid Initiated O-H Insertion/Aldol/Oxy-Cope Cascade for the Stereoselective Synthesis of Functionalized Oxacycles
Chinthapally, Kiran,Massaro, Nicholas P.,Sharma, Indrajeet
supporting information, p. 6340 - 6343 (2016/12/23)
A novel diazo-cascade approach has been developed for the synthesis of nine-membered oxacycles utilizing readily accessible β-hydroxy vinyl ketones and vinyl diazo esters. The Rh(II)-catalyzed cascade reaction begins with carbene O-H insertion followed by an intramolecular aldol cyclization to provide a substituted tetrahydrofuran intermediate that undergoes an oxy-Cope rearrangement to provide functionalized nine-membered oxacycles with complete stereoselectivity.
Synthesis of functionalized 1-azabicyclo[3.1.0]hexanes: Studies towards ficellomycin and its analogs
Chen, Gang,He, Zhi,Yudin, Andrei K.
, p. 1299 - 1310 (2016/10/06)
The molecule of antibiotic agent ficellomycin contains an intriguing array of functional groups assembled around a bicyclic aziridine core. To address the challenges of constructing ficellomycin derivatives, we have developed cycloamination methodology fo
