ChemInform Abstract: Short Synthesis of (.+-.)-Hirsutine: Direct Addition of Dimethyl Malonate Anion to a 1,4-Conjugate Iminium Salt of Appropriate 3- Ethylindolo(2,3-a)quinolizidine.

ChemInform ◽  
2010 ◽  
Vol 28 (24) ◽  
pp. no-no
Author(s):  
M. LOUNASMAA ◽  
J. MIETTINEN ◽  
P. HANHINEN ◽  
R. JOKELA
Keyword(s):  
Dimethyl Malonate ◽  
Iminium Salt ◽  
Direct Addition ◽  
Short Synthesis

A Short Synthesis of (+)-Brefeldin C via Enantioselective Radical Hydroalkynylation

2019 ◽  
Author(s):  
Lars Gnägi ◽  
Severin Vital Martz ◽  
Daniel Meyer ◽  
Robin Marc Schärer ◽  
Philippe Renaud
Keyword(s):  
Total Synthesis ◽  
Natural Product ◽  
Oxidation State ◽  
Single Step ◽  
Radical Process ◽  
Target Molecule ◽  
Short Synthesis ◽  
The One

<div><div><div><div><p>A very concise total synthesis of (+)-brefeldin C starting from 2-furanylcyclopentene is described. This approach is based on an unprecedented enantioselective radical hydroalkynylation process to introduce the two cyclopentane stereocenters in a single step. The use of a furan substituent allows to achieve a high trans diastereoselectivity during the radical process and it contains the four carbon atoms C1–C4 of the natural product in an oxidation state closely related to the one of the target molecule. The eight-step synthesis require six product purifications and it provides (+)-brefeldin C in 18% overall yield.</p></div></div></div></div>

A Short Synthesis of the Plant Alkaloid 4-Methyl-2,6-naphthyridine

2019 ◽  
Vol 16 (12) ◽  
pp. 931-934 ◽  
Author(s):  
Alexandra Kamlah ◽  
Franz Bracher
Keyword(s):  
Pyridine Ring ◽  
Cross Coupling ◽  
Antirrhinum Majus ◽  
New Synthesis ◽  
Short Synthesis ◽  
Regioselective Oxidation ◽  
Key Steps

: A new synthesis of the 2,6-naphthyridine alkaloid 4-methyl-2,6-naphthyridine from Antirrhinum majus has been developed. Key steps are a regioselective oxidation of 3-bromo-4,5- dimethylpyridine to the corresponding 4-formyl derivative, and the annulation of the second pyridine ring by Suzuki-Miyaura cross-coupling using (E)-2-ethoxyvinylboronic acid pinacol ester as a masked acetaldehyde equivalent. This protocol gives the alkaloid in four steps starting from commercially available 3,4-dimethylpyridine in 15% overall yield. This annulation protocol should be useful for the synthesis of other condensed pyridines as well.

P-Chiral 2-{1'-[Butyl(phenyl)phosphanyl]ferrocen-1-yl}-4-isopropyl-4,5-dihydrooxazoles: A Second Chirality Center in Catalytic System

2005 ◽  
Vol 70 (3) ◽  
pp. 361-369 ◽  
Author(s):  
Dušan Drahoňovský ◽  
Petr Štěpnička ◽  
Dalimil Dvořák
Keyword(s):  
Catalytic System ◽  
Asymmetric Induction ◽  
Dimethyl Malonate ◽  
Enantiomerically Pure

P-Chiral (S,RP)-2-{1'-[butyl(phenyl)phosphanyl]ferrocen-1-yl}-4-isopropyl-4,5-dihydrooxazole (6) and (S,SP)-2-{1'-[butyl(phenyl)phosphanyl]ferrocen-1-yl}-4-isopropyl-4,5-dihydrooxazole (7) were prepared by the procedure developed by Jugé, starting from enantiomerically pure (-)- or (+)-ephedrine and dichloro(phenyl)phosphine. Compounds 6 and 7 were examined for asymmetric induction in the Pd-catalyzed reaction of rac-1,3-diphenylallyl acetate with dimethyl malonate. The best results were obtained with 7 (98% ee), while 6 gave 82% ee.

scholarly journals CLytA-DAAO Chimeric Enzyme Bound to Magnetic Nanoparticles. A New Therapeutical Approach for Cancer Patients?

2021 ◽  
Vol 22 (3) ◽  
pp. 1477
Author(s):  
María Fuentes-Baile ◽  
Elizabeth Pérez-Valenciano ◽  
Pilar García-Morales ◽  
Camino de Juan Romero ◽  
Daniel Bello-Gil ◽  
...  
Keyword(s):  
Magnetic Nanoparticles ◽  
Colorectal Carcinoma ◽  
Acid Oxidase ◽  
Oxygen Species ◽  
Cell Models ◽  
Amino Acid Oxidase ◽  
Direct Addition ◽  
Alginate Capsules ◽  
Anti Cancer ◽  
The Stability

D-amino acid oxidase (DAAO) is an enzyme that catalyzes the oxidation of D-amino acids generating H2O2. The enzymatic chimera formed by DAAO bound to the choline-binding domain of N-acetylmuramoyl-L-alanine amidase (CLytA) induces cytotoxicity in several pancreatic and colorectal carcinoma and glioblastoma cell models. In the current work, we determined whether the effect of CLytA-DAAO immobilized in magnetic nanoparticles, gold nanoparticles, and alginate capsules offered some advantages as compared to the free CLytA-DAAO. Results indicate that the immobilization of CLytA-DAAO in magnetic nanoparticles increases the stability of the enzyme, extending its time of action. Besides, we compared the effect induced by CLytA-DAAO with the direct addition of hydrogen peroxide, demonstrating that the progressive generation of reactive oxygen species by CLytA-DAAO is more effective in inducing cytotoxicity than the direct addition of H2O2. Furthermore, a pilot study has been initiated in biopsies obtained from pancreatic and colorectal carcinoma and glioblastoma patients to evaluate the expression of the main genes involved in resistance to CLytA-DAAO cytotoxicity. Based on our findings, we propose that CLytA-DAAO immobilized in magnetic nanoparticles could be effective in a high percentage of patients and, therefore, be used as an anti-cancer therapy for pancreatic and colorectal carcinoma and glioblastoma.

ChemInform Abstract: A Short Synthesis of (.+-.)-Ricciocarpin a Using Intramolecular Reductive Michael Reaction.

ChemInform ◽  
2010 ◽  
Vol 29 (18) ◽  
pp. no-no
Author(s):  
K. TAKEDA ◽  
N. OHKAWA ◽  
K. HORI ◽  
T. KOIZUMI ◽  
E. YOSHII
Keyword(s):  
Michael Reaction ◽  
Short Synthesis

The application of vinylogous iminium salt derivatives to the regiocontrolled preparation of heterocyclic appended pyrazoles

Tetrahedron ◽  
2002 ◽  
Vol 58 (27) ◽  
pp. 5467-5474 ◽  
Author(s):  
John T Gupton ◽  
Stuart C Clough ◽  
Robert B Miller ◽  
Bradley K Norwood ◽  
Charles R Hickenboth ◽  
...  
Keyword(s):  
Iminium Salt

A short synthesis of naturally occurring and other analogues of plakinic acids that contain the 1,2-dioxolane group

1996 ◽  
Vol 37 (11) ◽  
pp. 1885-1888 ◽  
Author(s):  
A.J. Bloodworth ◽  
Brian D Bothwell ◽  
Andrew N Collins ◽  
Nicola L Maidwell
Keyword(s):  
Naturally Occurring ◽  
Short Synthesis
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