A samarium(II) iodide promoted tandem radical cyclization. The total synthesis of (.+-.)-hypnophilin and the formal synthesis of (.+-.)-coriolin

1988 ◽  
Vol 110 (15) ◽  
pp. 5064-5067 ◽  
Author(s):  
Thomas L. Fevig ◽  
Richard L. Elliott ◽  
Dennis P. Curran
Keyword(s):  
Total Synthesis ◽  
Radical Cyclization ◽  
Formal Synthesis

scholarly journals Expedient Access to Enantiopure Cyclopentanic Natural Products: Total Synthesis of (-)-Cyclonerodiol

2015 ◽  
Vol 10 (1) ◽  
pp. 1934578X1501000
Author(s):  
Carmen Pérez Morales ◽  
M. Mar Herrador ◽  
José F. Quílez del Moral ◽  
Alejandro F. Barrero
Keyword(s):  
Natural Products ◽  
Total Synthesis ◽  
Radical Cyclization ◽  
Formal Synthesis ◽  
Common Precursor ◽  
Enantiospecific Synthesis ◽  
Optically Pure

Following the principles of collective total synthesis, a number of natural products sharing an optically pure, multifunctional, cyclopentanic core were synthesized from a common precursor: plinol A (1). This intermediate was efficiently obtained in only four steps from (-)-linalool (2) using as the key step a Ti(III)-mediated diastereoselective radical cyclization. The feasibility of this approach was confirmed with the expedient enantiospecific synthesis of cyclonerodiol (3), and the formal synthesis of chocol G (4) and piperitone (5).

ChemInform Abstract: Total Synthesis of (-)-γ-Lycorane Using Diastereoselective 5-endo-trig Radical Cyclization of N-Vinylic α-Halo Amides.

ChemInform ◽  
2010 ◽  
Vol 30 (13) ◽  
pp. no-no
Author(s):  
Masazumi Ikeda ◽  
Shinji Ohtani ◽  
Tatsunori Sato ◽  
Hiroyuki Ishibashi
Keyword(s):  
Total Synthesis ◽  
Radical Cyclization

scholarly journals Stereocontrolled total synthesis of (+)-vinblastine

2003 ◽  
Vol 75 (1) ◽  
pp. 29-38 ◽  
Author(s):  
Satoshi Yokoshima ◽  
T. Ueda ◽  
S. Kobayashi ◽  
A. Sato ◽  
Takeshi Kuboyama ◽  
...  
Keyword(s):  
Total Synthesis ◽  
Coupling Reaction ◽  
Radical Cyclization ◽  
Critical Coupling ◽  
Efficient Manner ◽  
Complete Control ◽  
Highly Efficient ◽  
Indole Synthesis

Stereocontrolled total synthesis of (+)-vinblastine (1) has been achieved using a novel radical-mediated indole synthesis developed in our laboratories. The isothiocyanate 18, prepared readily from quinoline 17, underwent a facile addition of the malonate anion to give 19. The o-alkenylthioanilide 19 was then converted to indole 20 by radical cyclization and protection. (−)-Vindoline (2) was prepared from this key intermediate 20 in a highly efficient manner. The indole core of the 11-membered intermediate 3 was constructed similarly from quinoline. The critical coupling reaction between 2 and the chloroindolenine derived from 3 proceeded with complete control of stereochemistry to give the desired product 66 in 97 % yield, which could be successfully converted to (+)-vinblastine (1).

Chemoenzymatic Formal Total Synthesis of Pancratistatin from Narciclasine-Type Compounds via Myers Transposition: Model Study for a Short Conversion of Narciclasine to Pancratistatin

Synlett ◽  
2017 ◽  
Vol 28 (20) ◽  
pp. 2896-2900 ◽  
Author(s):  
Ringaile Lapinskaite ◽  
Mukund Ghavre ◽  
Chelsea Rintelmann ◽  
Korey Bedard ◽  
Helen Dela Paz ◽  
...  
Keyword(s):  
Total Synthesis ◽  
Recombinant Strain ◽  
Optical Purity ◽  
Allylic Alcohol ◽  
Formal Synthesis ◽  
Toluene Dioxygenase ◽  
Single Isomer ◽  
Model Study ◽  
New Compounds ◽  
Subsequent Opening

A formal total synthesis of pancratistatin was accomplished by conversion of advanced intermediates, used in the synthesis of narciclasine, to pancratistatin precursors via Myers’ reductive transposition as the key strategic step. The synthesis began with the whole cell fermentation of m-dibromobenzene with JM109(pDTG601a), a recombinant strain that over-expresses toluene dioxygenase, which provided the corresponding cis-dihydrodiol 16 as a single isomer with complete optical purity. The key reductive transposition of the allylic alcohol 8a to olefin 9a allowed for further installation of the C-1/C-2 trans-diol, ­required for the pancratistatin scaffold, through the introduction of a cyclic sulfate and its subsequent opening. The formal synthesis of pancratistatin was accomplished in 14 steps (12 operations) from commercially available m-dibromobenzene. Experimental and spectral data are provided for all new compounds.

Bioinspired Total Synthesis of Marine Anti-Cancer Meroterpenoids Dysideanone B and Dysiherbol A and Structure Revision of Dysiherbol A

Synlett ◽  
2021 ◽  
Author(s):  
Zhaoyong Lu ◽  
Chuanke Chong
Keyword(s):  
Total Synthesis ◽  
Heck Reaction ◽  
Recent Progress ◽  
Benzyl Bromide ◽  
Radical Cyclization ◽  
Ethoxy Group ◽  
Anti Cancer ◽  
Structure Revision ◽  
A Site ◽  
Intramolecular Heck Reaction

Our recent progress on the total synthesis of marine anti-cancer sesquiterpene quinone/hydroquinone dysideanone B and dysiherbol A was briefly highlighted. This success relied on some key transformations. The union of the terpene and quinone/hydroquinone moieties was realized through a site and stereoselective α-position alkylation of Wieland–Miescher ketone derivative with a bulky benzyl bromide. The 6/6/6/6-tetracycle of dysideanone B was constructed using an intramolecular radical cyclization and the 6/6/5/6-fused core structure of dysiherbol A was forged by an intramolecular Heck reaction, respectively. The possible origin of ethoxy group in dysideanone B was revealed by mimicking the isolation conditions at a late-stage. The structure of dysiherbol A was revised through the total synthesis of this natural product. Schmalz’s synthesis of dysiherbol A was also included.

ChemInform Abstract: TOTAL SYNTHESIS OF SATIVENE AND COPACAMPHENE VIA A FREE RADICAL CYCLIZATION

1977 ◽  
Vol 8 (2) ◽  
pp. no-no
Author(s):  
P. BAKUZIS ◽  
O. O. S. CAMPOS ◽  
M. L. F. BAKUZIS
Keyword(s):  
Free Radical ◽  
Total Synthesis ◽  
Radical Cyclization
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