FURTHER DEGRADATION REACTIONS OF ANNOTININE

1955 ◽  
Vol 33 (5) ◽  
pp. 849-860 ◽  
Author(s):  
F. A. L. Anet ◽  
Léo Marion
Keyword(s):  
Amino Acid ◽  
Benzene Ring ◽  
Potassium Permanganate ◽  
Lactone Ring ◽  
Neutral Substance ◽  
Unsaturated Lactone ◽  
Degradation Reactions ◽  
Vinyl Group ◽  
Color Reactions ◽  
Chromous Chloride

Both the hydroxylactone obtained by the action of chromous chloride on annotinine chlorohydrin, and the unsaturated lactone B prepared by the action of the same reagent on the hydroxylactone, contain a secondary nitrogen and a vinyl group. The unsaturated lactone A which accompanies the hydroxylactone is a cyclic allylamine which on oxidation with potassium permanganate yields an amino acid C14H19O4N. These facts make it possible to explain the reaction of chromous chloride with annotinine chlorohydrin. The amino acid can be de-hydrogenated to an acid containing a free carboxyl and a lactamic grouping (C14H15O3N) but no longer containing a lactone ring. The lactamic acid which seems to contain a benzene ring is readily decarboxylated to a neutral substance C13H15ON, showing color reactions and ultraviolet absorption similar to those of strychnine.

Abstract 90: Inimitable Ouabain: The Endogenous Circulating Cardiotonic Steroid that Singularly Stimulates Sodium Potassium Pump Activity at Low Doses

2017 ◽  
Vol 121 (suppl_1) ◽  
Author(s):  
Yeon Jae Kim ◽  
Elisha Hamilton ◽  
William Hannam ◽  
Chia-Chi Liu ◽  
Rachel Teh ◽  
...  
Keyword(s):  
Low Dose ◽  
Lactone Ring ◽  
Cardiac Contractility ◽  
Cancer Cell Line ◽  
Structural Components ◽  
Sodium Potassium ◽  
Sugar Moiety ◽  
Unsaturated Lactone ◽  
Sodium Potassium Pump ◽  
The Difference

Rationale: Cardiotonic steroids (CTS), such as digoxin, have been used to treat heart failure (HF) for over 200 years. They inhibit the sodium-potassium pump (NKP), and increase cardiac contractility by inhibiting efflux of sodium through the pump (“digitalis hypothesis”). CTS possess three structural components: a saturated/unsaturated lactone ring, steroid core, and sugar moiety, each of which may be involved in NKP inhibition/stimulation. It is now known that inhibition of the NKP in patients with HF increases mortality, and all major beneficial treatments increase its activity. Endogenous circulating CTS such as ouabain are generally thought to inhibit the NKP, despite studies sporadically reporting ouabain-induced pump stimulation. This study aims to identify whether ouabain-induced pump stimulation occurs, and if so, which structural components are involved in causing pump stimulation. Methods & Results: Cardiac myocytes were isolated from male New Zealand White rabbits, placed in a Tyrode’s solution, and whole-cell patch clamped. They were exposed to 0-30nM ouabain, 0-50nM dihydroouabain (ouabain with a saturated lactone ring) or 0-500nM ouabagenin (ouabain lacking a sugar moiety) for 1 min, followed by a potassium-free solution, with the difference in current yielding the NKP current. Compared to the 0.47±0.05 pA/pF Tyrode’s solution control (n=11), 5nM ouabain significantly increased NKP current to 0.69±0.09 pA/pF ( P <0.05, n=6). Exposure to dihydroouabain or ouabagenin did not significantly change NKP current in the studied concentration range. Cell viability assays carried out on the breast cancer cell line MCF7, which have an NKP structure extremely similar to that of cardiomyocytes, showed significantly elevated viability above control values (n=2) following 24h treatment with 0-9nM ouabain; maximum viability was 116±5% at 0.28nM ( P <0.05, n=4). A significant change in viability was not observed for ouabagenin or digoxin in the same concentration range. Conclusion: Low-dose ouabain uniquely stimulates NKP activity. Low-dose dihydroouabain and ouabagenin do not, suggesting that a sugar moiety and unsaturated lactone ring are required for pump stimulation. Ouabain in its unaltered form may be a potential treatment for HF.

Importance of the Position of Vinyl Group on β-Cyclodextrin for the Effective Imprinting of Amino Acid Derivatives and Oligopeptides in Water

2006 ◽  
Vol 39 (7) ◽  
pp. 2460-2466 ◽  
Author(s):  
Tomo Osawa ◽  
Kazumi Shirasaka ◽  
Takahiko Matsui ◽  
Shinji Yoshihara ◽  
Tomohiro Akiyama ◽  
...  
Keyword(s):  
Amino Acid ◽  
Amino Acid Derivatives ◽  
Vinyl Group

A Study of Substituent Effect on the Oxidative Strengths of N-Chloroarenesulphonamides: Kinetics of Oxidation of Leucine and Isoleucine in Aqueous Acid Medium

2004 ◽  
Vol 59 (1) ◽  
pp. 63-72 ◽  
Author(s):  
Mahesha Shetty ◽  
B. Thimme Gowda
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Ionic Strength ◽  
Acid Medium ◽  
Benzene Ring ◽  
Thermodynamic Data ◽  
Substituent Effect ◽  
Kinetics Of Oxidation ◽  
Aqueous Acid ◽  
Kinetics Of

Abstract To study the variation of oxidative strengths of N-chloro-arenesulphonamides with substitution in the benzene ring, six mono- and five di-substituted N-chloro-arenesulphonamides are employed as oxidants for studying the kinetics of oxidation of two neutral amino acids, L-leucine and Lisoleucine in aqueous acid medium. The N-chloro-arenesulphonamides studied are of the constitution: ArSO2NaNCl·H2O (where Ar = C6H5, 4-CH3C6H4, 4-C2H5C6H4, 4-FC6H4, 4-ClC6H4, 4-BrC6H4, 2,3-(CH3)2C6H3, 2,4-(CH3)2C6H3, 2-CH3-4-ClC6H3, 2,4-Cl2C6H3, and 3,4-Cl2C6H3). The reactions show second order kinetics in [oxidant], fractional order in [amino acid] and inverse dependence on [H+]. Addition of the reduced product of the oxidants or variation in ionic strength of the medium has no significant effect on the rates of oxidations. A two-pathway mechanism is considered to explain the experimental results. Effective oxidizing species of the oxidants is Cl+ in different forms. Therefore the oxidising strengths of N-chloro-arenesulphonamides depend on the ease with which Cl+ is released from them. The study reveals that the introduction of substituent in the benzene ring of the oxidant affects both the kinetic and thermodynamic data for the oxidations The electron releasing groups such as CH3 generally inhibit the rates, while electron-withdrawing groups such as Cl enhance this ability, as the electron withdrawing groups ease the release of Cl+ from the reagents and hence increase the oxidising strengths. The on Ea and logA and validity of the Hammett and isokinetic relationships for the oxidations are also analysed.

scholarly journals Crystal structure of 5-O-benzoyl-2,3-O-isopropylidene-D-ribono-1,4-lactone

2017 ◽  
Vol 73 (3) ◽  
pp. 407-409
Author(s):  
Adailton J. Bortoluzzi ◽  
Gustavo P. Silveira ◽  
Marcus M. Sá
Keyword(s):  
Crystal Structure ◽  
Benzene Ring ◽  
Absolute Configuration ◽  
Title Compound ◽  
Benzoyl Chloride ◽  
Lactone Ring ◽  
Three Dimensional ◽  
Acylation Reaction ◽  
Compound C ◽  
Dimensional Network

In the title compound, C15H16O6, obtained from the acylation reaction between 2,3-O-isopropylidene-D-ribono-1,4-lactone and benzoyl chloride, the known absolute configuration for the lactone moiety of the ester substituent has been confirmed. The five-membered rings of the bicyclic lactone–dioxolane moiety both show envelope conformations and form a dihedral angle of 19.82 (7)° between the lactone ring and the benzene ring. In the crystal, molecules of the acylated sugar are linked by very weak intermolecular C—H...O interactions, forming a three-dimensional network.

scholarly journals (E)-13-(2-Bromophenyl)micheliolide

2014 ◽  
Vol 70 (3) ◽  
pp. o251-o252
Author(s):  
Narsimha Reddy Penthala ◽  
Shobanbabu Bommagani ◽  
Venumadhav Janganati ◽  
Sean Parkin ◽  
Peter A. Crooks
Keyword(s):  
Hydrogen Bonding ◽  
Benzene Ring ◽  
Dihedral Angle ◽  
Title Compound ◽  
Heck Reaction ◽  
Lactone Ring ◽  
Reaction Conditions ◽  
Compound C ◽  
The Mean ◽  
Graph Set

The title compound, C21H23BrO3[systematic name: (3E,3aS,6Z,9R,9aS,9bS)-3-(2-bromobenzylidene)-9-hydroxy-6,9-dimethyl-3,3a,4,5,7,8,9,9a-octahydroazuleno[4,5-b]furan-2(9bH)-one] was prepared by the reaction of 1-bromo-2-iodobenzene with micheliolide [systematic name: (3aS,R,9aS,9bS,Z)-9-hydroxy-6,9-dimethyl-3-methylene-3,3a,4,5,7,8,9,9a-octahydroazuleno[4,5-b]furan-2(9bH)-one] under Heck reaction conditions. The title compound exhibits intramolecular O—H...O hydrogen bonding between the hydroxy group and the lactone ring O atom, forming a ring of graph-set motifS(6). The 2-bromophenyl group istransto the lactone ring, indicating that this is theEisomer (geometry of the exocyclic C=C bond). The dihedral angle between the benzene ring of the 2-bromophenyl moiety and the mean plane of the lactone ring is 51.68 (7)°.

ANNOTININE: THE REACTIONS OF THE CYCLIC ETHER FUNCTION

1954 ◽  
Vol 32 (3) ◽  
pp. 268-279 ◽  
Author(s):  
H. L. Meier ◽  
P. D. Meister ◽  
Léo Marion
Keyword(s):  
Chromic Acid ◽  
Cyclic Ether ◽  
The Other ◽  
Amino Group ◽  
Imino Group ◽  
Unsaturated Lactone ◽  
Clemmensen Reduction ◽  
Secondary Amino ◽  
Concentrated Solution ◽  
Chromous Chloride

Treatment of annotinine chlorohydrin with chromous chloride has been found to produce not only the already reported unsaturated lactone A (C16H21O2N), but also a second unsaturated lactone B (C16H21(23)O2N), and a hydroxylactone (C16H23O3N). Under the action of a concentrated solution of the same reagent the hydroxylactone is converted to the unsaturated lactone B. On hydrogenation the latter gives a dihydrolactone B which seems to contain a secondary amino group. Annotinine hydrate on treatment with thionyl chloride gives an unsaturated chlorolactone (C16H20O2NCl) which can be hydrogenated and subsequently dechlorinated to produce a third lactone C, different from either of dihydrolactones A or B, but which like the latter seems to contain an imino group. Oxidation of annotinine hydrate with chromic acid produces a hydroxyketone which can be converted into an oxime and, therefore, one of the hydroxyls of the hydrate is secondary while the other is probably tertiary. On the other hand, oxidation of annotinine with potassium permanganate gives rise to a lactam which by the Clemmensen reduction is converted to a mixture of lactam chlorohydrin and dihydrolactone A.

scholarly journals Structure and Hirshfeld surface analysis of the salt N,N,N-trimethyl-1-(4-vinylphenyl)methanaminium 4-vinylbenzenesulfonate

2019 ◽  
Vol 75 (7) ◽  
pp. 946-950 ◽  
Author(s):  
C. John McAdam ◽  
Lyall R. Hanton ◽  
Stephen C. Moratti ◽  
Jim Simpson ◽  
Ravindra N. Wickramasinhage
Keyword(s):  
Hydrogen Bonds ◽  
Benzene Ring ◽  
Surface Analysis ◽  
Title Compound ◽  
Hirshfeld Surface ◽  
Hirshfeld Surface Analysis ◽  
Asymmetric Unit ◽  
Ring Plane ◽  
The Individual ◽  
Vinyl Group

In the title compound, the asymmetric unit comprises an N,N,N-trimethyl-1-(4-vinylphenyl)methanaminium cation and a 4-vinylbenzenesulfonate anion, C12H18N+·C8H7O3S−. The salt has a polymerizable vinyl group attached to both the cation and the anion. The methanaminium and vinyl substituents on the benzene ring of the cation subtend angles of 86.6 (3) and 10.5 (9)° to the ring plane, while the anion is planar excluding the sulfonate O atoms. The vinyl substituent on the benzene ring of the cation is disordered over two sites with a refined occupancy ratio of 0.542 (11):0.458 (11). In the crystal, C—H...O hydrogen bonds dominate the packing and combine with a C—H...π(ring) contact to stack the cations and anions along the a-axis direction. Hirshfeld surface analysis of the salt and of the individual cation and anion components is also reported.

The Responses of Onion and Lily Mitosis to Coumarin and Parasorbic Acid

1947 ◽  
Vol 23 (3-4) ◽  
pp. 292-297
Author(s):  
IVOR CORNMAN
Keyword(s):  
Aqueous Solution ◽  
Benzene Ring ◽  
Lactone Ring ◽  
Saturated Solution ◽  
Saturated Aqueous Solution ◽  
Benzene Derivatives ◽  
Binucleate Cells

1. In Allium and Lilium roots, saturated aqueous solution of coumarin produced a disruption of the metaphase typical of many benzene derivatives, viz. suppression of the spindle, splitting and shortening of the chromosomes, with retarded division of the centromere. The resultant polyploid nuclei and binucleate cells resumed division when the roots were returned to water. 2. Saturated solution of parasorbic acid slowed Allium mitosis, but caused no abnormalities. 3. Both coumarin and parasorbic acid eventually prevented the inception of mitosis, and this suppression of prophases persisted for several hours after removal of the agent. 4. The results are in agreement with prior evidence that in some configurations the benzene ring disrupts mitosis whereas the lactone ring inhibits growth.

scholarly journals 8-O-Acetyl-8-epi-9-deoxygoniopypyrone

2012 ◽  
Vol 68 (4) ◽  
pp. o1072-o1073
Author(s):  
Hoong-Kun Fun ◽  
Suchada Chantrapromma ◽  
Uma Prawat ◽  
Nawong Boonnak ◽  
Ibrahim Abdul Razak
Keyword(s):  
Benzene Ring ◽  
Title Compound ◽  
Lactone Ring ◽  
Chair Conformation ◽  
Pyran Ring ◽  
Π Interactions ◽  
Envelope Conformation ◽  
Acetyl Group

The title compound (systematic name: 7-oxo-3-phenyl-2,6-dioxabicyclo[3.3.1]nonan-4-yl acetate), C15H16O5, is a styryllactone derivative which was isolated fromGoniothalamus macrophyllus. The molecule has two fused rings consisting of a tetrahydro-2H-pyran and a lactone ring, with the benzene ring and the acetyl group attached to the tetrahydro-2H-pyran ring. The tetrahydro-2H-pyran ring is in a standard chair conformation, whereas the lactone ring is in an envelope conformation. In the crystal, molecules are linked by weak C—H...O interactions into sheets parallel to theacplane. Weak C—H...π interactions are also observed.

Synthesis of some westphalen-type cardenolide analogs

1982 ◽  
Vol 47 (1) ◽  
pp. 108-116 ◽  
Author(s):  
Pavel Kočovský ◽  
Pavel Drašar ◽  
Vladimír Pouzar ◽  
Miroslav Havel
Keyword(s):  
Lactone Ring ◽  
Cardiotonic Activity ◽  
Unsaturated Lactone ◽  
Tributyltin Hydride ◽  
Key Steps

Synthesis of the lactone II and thiazole XXIII as models of compounds with cardiotonic activity is described. The key steps in the synthesis of the lactone II are Westphalen rearrangement (XII - XIII), construction of unsaturated lactone ring by intramolecular Witting reaction (XV XIX) and removal of the halogen from 6β-position by reduction with tributyltin hydride. XXIII was obtained from the bromo ketone XXII by treatment with ethyl thioxamate.

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