SOME OXIDATION REACTIONS OF DELCOSINE

1957 ◽  
Vol 35 (4) ◽  
pp. 397-408 ◽  
Author(s):  
Ragini Anet ◽  
D. W. Clayton ◽  
Léo Marion
Keyword(s):  
Acetic Acid ◽  
Silver Oxide ◽  
Chromic Acid ◽  
Mercuric Acetate ◽  
Membered Ring ◽  
Oxidation Reactions ◽  
Ethyl Group ◽  
Compound C ◽  
Ring Oxidation ◽  
Group B

The alkaloid delcosine was oxidized by chromic acid in acetic acid, and also by the Oppenauer reaction, to dehydrodelcosine in which the carbonyl was shown by infrared absorption to be in a pentatomic ring. Oxidation of the alkaloid with silver oxide gave two products: (a) N-desethyldelcosine, which could be N-acetylated or converted back to the original base by ethylation, thus proving the presence of an N-ethyl group; (b) a compound, C24H37O7N, the properties of which agreed best with those of an internal ether, i.e., anhydrohydroxydelcosine. The action of N-bromosuccinimide on the alkaloid produced the same two compounds as silver oxide, plus a derivative, C22H33O7N, that proved to be N-desethyl-anhydrohydroxydelcosine. Potassium permanganate oxidized delcosine to a product, C22H31O7N, that had lost the N-ethyl group, contained the internal ether, and also a carbonyl in a five-membered ring. This same product was obtained on similar oxidation of N-desethyl-anhydrohydroxydelcosine. Oxidation of delcosine with mercuric acetate gave N-desethyldelcosine and N-desethyl-anhydrohydroxydelcosine, together with a compound that was very soluble in water and proved to be the carbinolamine formed by hydroxylation of the methylene in the N-ethyl group. These results are discussed in terms of a structure that is tentatively advanced for delcosine.

scholarly journals Microwave synthesis and molecular re-arrangement of a grisadienone and its derivatives

2011 ◽  
Author(s):  
◽  
Thandekile Sithembile Ngcobo
Keyword(s):  
Acetic Acid ◽  
Acetic Anhydride ◽  
Chromic Acid ◽  
Selenium Dioxide ◽  
Acid Oxidation ◽  
Microwave Assisted ◽  
Chromic Acid Oxidation ◽  
Compound C ◽  
Acid Compound ◽  
Yellow Compound

ortho-Deoxygrisan (38), a spirodienone was synthesised from bisphenol (42) using both conventional and microwave assisted methods. The bisphenol (42) was synthesised from phenol (52) by conventional and microwave assisted methods. Benzophenone (43) was synthesised from compound (49) which in turn was synthesised from compound (53) by chromic acid oxidation in acetic anhydride or acetic acid. Compound (53) was synthesised from bisphenol (42) by mono-acetylation method. OH OH OH O O OH O OH 43 OAc O OAc 38 42 52 OH OAc 49 53 Acid-catalysed rearrangement of ortho-deoxygrisan (38) in the absence of light was investigated. Chromatography of the reaction mixture afforded compound (D) as a major component. O D OAc Attempts to synthesise ortho-grisan (50) from benzophenone (43) were unsuccessful. O O 50 Microwave assisted selenium dioxide oxidation of compound (53) gave a yellow compound C. The spectra of this compound were very similar to the spectra of ortho-deoxygrisan (38). However, selenium dioxide was reacted with compound (53) in the absence of microwave to give a yellow solid B. The 1H NMR spectral data of this compound led to the proposed structure B for it. O vii O Se O B

scholarly journals 14,15-Didehydrohellebrigenin

2012 ◽  
Vol 68 (6) ◽  
pp. o1614-o1615
Author(s):  
Tong Yu ◽  
Hai-Yan Tian ◽  
Xiao-Feng Yuan ◽  
Shu-Zhi Hu ◽  
Ren-Wang Jiang
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Title Compound ◽  
Lactone Ring ◽  
Three Dimensional ◽  
Membered Ring ◽  
Envelope Conformation ◽  
Compound C ◽  
Dimensional Network ◽  
Hydroxy Groups

The title compound, C24H30O5, is the didehydro product of the steroid hellebrigenin (systematic name: 3β,5,14-trihydroxy-19-oxo-5β-bufa-20,22-dienolide). It consists of three cyclohexane rings (A, B and C), a five-membered ring (D) and a six-membered lactone ring (E). The stereochemistry of the ring junctions are A/B cis, B/C trans and C/D cis. Cyclohexane rings A, B and C have normal chair conformations. The five-membered ring D with the C=C bond adopts an envelope conformation. Lactone ring E is essentially planar with a mean derivation of 0.006 (4) Å and is β-oriented at the C atom of ring D to which it is attached. There is an O—H...O hydrogen bond in the molecule involving the hydroxy groups. In the crystal, O—H...O hydrogen bonds link the molecules into chains propagating along [010]. The chains are linked by C—H...O contacts into a three-dimensional network.

scholarly journals 2-Oxo-2H-chromen-7-yl 4-methylbenzoate

IUCrData ◽  
2018 ◽  
Vol 3 (7) ◽  
Author(s):  
Abdoulaye Djandé ◽  
Akoun Abou ◽  
Félix Kini ◽  
Konan René Kambo ◽  
Michel Giorgi
Keyword(s):  
Hydrogen Bond ◽  
Title Compound ◽  
Acute Angle ◽  
Membered Ring ◽  
Hirshfeld Surface ◽  
Supramolecular Interactions ◽  
Stacking Interactions ◽  
Weak Hydrogen Bond ◽  
Compound C ◽  
Benzene Rings

In the title compound, C17H12O4, the benzoate ring is oriented at an acute angle of 60.14 (13)° relative to the coumarin plane (r.m.s. deviation = 0.006 Å). This conformation is stabilized by an intramolecular C—H...O weak hydrogen bond, which forms a five-membered ring. Also present are π–π stacking interactions between neighbouring pyrone and benzene rings [centroid-to-centroid distances in the range 3.6286 (1)–3.6459 (1) Å] and C=O...π interactions [O...centroid distances in the range 3.2938 (1)–3.6132 (1) Å]. Hirshfeld surface analysis has been used to confirm and quantify the supramolecular interactions.

scholarly journals Crystal structure of 3-amino-2-ethylquinazolin-4(3H)-one

2015 ◽  
Vol 71 (9) ◽  
pp. o650-o651
Author(s):  
Gamal A. El-Hiti ◽  
Keith Smith ◽  
Amany S. Hegazy ◽  
Mohammed Baashen ◽  
Benson M. Kariuki
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Torsion Angle ◽  
Title Compound ◽  
Ethyl Group ◽  
Π Interactions ◽  
Step Structure ◽  
Compound C ◽  
Centroid Distance

The molecule of the title compound, C10H11N3O, is planar, including the ethyl group, as indicated by the N—C—C—C torsion angle of 1.5 (2)°. In the crystal, inversion-related molecules are stacked along theaaxis. Molecules are oriented head-to-tail and display π–π interactions with a centroid-to-centroid distance of 3.6664 (8) Å. N—H...O hydrogen bonds between molecules generate a `step' structure through formation of anR22(10) ring.

scholarly journals N-Ethyl-2,2-dimethyl-N-(3-methylphenyl)propanamide

2014 ◽  
Vol 70 (2) ◽  
pp. o223-o223 ◽  
Author(s):  
B. S. Palakshamurthy ◽  
P. A. Suchetan ◽  
S Sreenivasa ◽  
N. K. Lokanath ◽  
T Madhu Chakrapani Rao
Keyword(s):  
Title Compound ◽  
Ethyl Group ◽  
Axis Direction ◽  
Π Interactions ◽  
Compound C

In the title compound, C14H21NO, the conformation across the N—C(O) bond issyn-periplanar, the C—N—C—C torsion being −5.9 (5)°. The atoms of the ethyl group attached to the N atom are disordered over two sets of sites with occupancy ratios of 0.65 (2):0.35 (2) (CH2) and 0.689 (14):0.311 (14) (CH3)are linked by very weak C—H...O interactions formingC(8) chains along [001]. C—H...π interactions link the molecules along thec-axis direction.

scholarly journals Crystal structure of ethyl 2-{4-[(5-chloro-1-benzofuran-2-yl)methyl]-3-methyl-6-oxo-1,6-dihydropyridazin-1-yl}acetate

2015 ◽  
Vol 71 (5) ◽  
pp. o291-o292 ◽  
Author(s):  
Youness Boukharsa ◽  
Lahcen El Ammari ◽  
Jamal Taoufik ◽  
Mohamed Saadi ◽  
M'hammed Ansar
Keyword(s):  
Crystal Structure ◽  
Dihedral Angle ◽  
Title Compound ◽  
Three Dimensional ◽  
Ring System ◽  
Maximum Deviation ◽  
Ethyl Group ◽  
Compound C ◽  
Dimensional Network

In the title compound, C18H17ClN2O4, the dihedral angle between the benzofuran ring system [maximum deviation 0.014 (2) Å] and the oxopyradizine ring is 73.33 (8)°. The structure is characterized by disorder of the ethyl group, which is split into two parts, with a major component of 0.57 (3), and the acetate carbonyl O atom, which is statistically disordered. In the crystal, the molecules are linked by C—H...O interactions, forming a three-dimensional network.

THE REACTION OF DIETHYL AZODICARBOXYLATE WITH DIHYDROGELSEMINE

1955 ◽  
Vol 33 (4) ◽  
pp. 604-609 ◽  
Author(s):  
Thelma Habgood ◽  
Léo Marion
Keyword(s):  
Infrared Spectrum ◽  
Methyl Ether ◽  
Sodium Borohydride ◽  
Lithium Aluminum Hydride ◽  
Chromic Acid ◽  
Aluminum Hydride ◽  
Membered Ring ◽  
Lithium Aluminum ◽  
Diethyl Azodicarboxylate ◽  
Methylene Group

Dihydrogelsemine reacts with diethyl azodicarboxylate yielding a carbinolamine which forms a methyl ether. Both this ether and the carbinolamine base can be oxidized by chromic acid to the same neutral lactam. That there has been no rearrangement of the carbon skeleton during these reactions is shown by reduction of the methyl ether of the carbinolamine with sodium borohydride to dihydrogelsemine and by reduction of the lactam with lithium aluminum hydride to tetrahydrodesoxygelsemine. It is concluded that both dihydrogelsemine and gelsemine contain a methylene group adjacent to N(b), and from the infrared spectrum of the lactam of dihydrogelsemine, N(b) appears to be part of a five-membered ring.

The chemistry of hop constituents. Part XL. Structure of a five-membered-ring oxidation product of colupulone

1974 ◽  
pp. 36 ◽  
Author(s):  
Jean Coates ◽  
Derek R. J. Laws ◽  
John A. Elvidge
Keyword(s):  
Oxidation Product ◽  
Membered Ring ◽  
Ring Oxidation
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