Synthesis of a biologically active isomer of frontalin and some new products from acylative decarboxylation of 3-methyltricarballylic acid

1990 ◽  
Vol 68 (5) ◽  
pp. 782-786 ◽  
Author(s):  
George M. Strunz ◽  
Chao-Mei Yu ◽  
Li Ya ◽  
Peter S. White ◽  
E. A. Dixon
Keyword(s):  
Acetic Anhydride ◽  
Functional Groups ◽  
Bark Beetles ◽  
New Products ◽  
Major Product ◽  
Biologically Active ◽  
Catalysed Reaction ◽  
Active Isomer ◽  
Pheromone Analogue ◽  
Simple Manipulation

2-Acetonyl-2-methylsuccinic anhydride, 3, the major product from base-catalysed reaction of 3-methyltricarballylic acid with acetic anhydride, was converted by simple manipulation of functional groups into 1,5-dimethyl-2,7-dioxabicyclo[3.2.1]octane. This bicyclic ketal (6) is isomeric with frontalin, 7, an aggregation pheromone for Dendroctonus bark beetles. It elicited electroantennogram responses in D. ponderosae and D. rufipennis. Besides 3 and the known compounds, 4 and 5, two new minor products, 8 and 9, were identified from base-catalysed acylative decarboxylation of 3-methyltricarballylic acid. Keywords: pheromone analogue, Dendroctonus, bark beetles.

scholarly journals Study of the biologically active acyclic ureas by nuclear magnetic resonance

2020 ◽  
Vol 100 (4) ◽  
pp. 60-74
Author(s):  
А.А. Bakibaev ◽  
◽  
М.Zh. Sadvakassova ◽  
V.S. Malkov ◽  
R.Sh. Еrkasov ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Functional Groups ◽  
13C Nmr ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
Biologically Active ◽  
Resonance Spectroscopy ◽  
13C Nmr Spectra ◽  
Nuclear Magnetic

A wide variety of acyclic ureas comprising alkyl, arylalkyl, acyl, and aryl functional groups are investigated by nuclear magnetic resonance spectroscopy. In general, spectral characteristics of more than 130 substances based on acyclic ureas dissolved in deuterated dimethyl sulfoxide at room temperature are studied. The re-sults obtained based on the studies of 1H and 13C NMR spectra of urea and its N-alkyl-, N-arylalkyl-, N-aryl- and 1,3-diaryl derivatives are presented, and the effect of these functional groups on the chemical shifts in carbonyl and amide moieties in acyclic urea derivatives is discussed. An introduction of any type of substitu-ent (electron-withdrawing or electron-donating) into urea molecule is stated to result in a strong upfield shift in 13C NMR spectra relatively to unsubstituted urea. A strong sensitivity of NH protons to the presence of acyl and aryl groups in nuclear magnetic resonance spectra is pointed out. In some cases, qualitative depend-encies between the chemical shifts in the NMR spectra and the structure of the studied acyclic ureas are re-vealed. A summary of the results on chemical shifts in the NMR spectra of the investigated substances allows determining the ranges of chemical shift variations of the key protons and carbon atoms in acyclic ureas. The literature describing the synthesis procedures are provided. The results obtained significantly expand the methods of reliable identification of biologically active acyclic ureas and their metabolites that makes it promising to use NMR spectroscopy both in biochemistry and in clinical practice.

Biologically active acyclonucleoside analogues. II. The synthesis of 9-[[2-hydroxy-1-(hydroxymethyl)ethoxy]methyl]guanine (BIOLF-62)

1982 ◽  
Vol 60 (24) ◽  
pp. 3005-3010 ◽  
Author(s):  
Kelvin K. Ogilvie ◽  
Ukken O. Cheriyan ◽  
Bruno K. Radatus ◽  
Kendall O. Smith ◽  
Karen S. Galloway ◽  
...  
Keyword(s):  
Chemical Synthesis ◽  
Functional Groups ◽  
Biologically Active ◽  
Nucleoside Analogues ◽  
Naturally Occurring

The chemical synthesis of 9-[[2-hydroxy-1-(hydroxymethyl)ethoxy]methyl]guanine is described. This compound, known as BIOLF-62, is active against herpesviruses. This compound is a member of a novel class of nucleoside analogues which lack a rigid carbohydrate ring, but which possess all of the functional groups of naturally occurring deoxynucleosides.

THE SYNTHESIS OF α-MONOFLUOROALKANOIC ACIDS

1965 ◽  
Vol 43 (6) ◽  
pp. 1700-1713 ◽  
Author(s):  
F. L. M. Pattison ◽  
R. L. Buchanan ◽  
F. H. Dean
Keyword(s):  
Functional Groups ◽  
Hydrogen Fluoride ◽  
Biologically Active ◽  
Fluorine Compounds ◽  
Perchloryl Fluoride

α-Monofluoroalkanoic acids are important intermediates in the synthesis of biologically active fluorine compounds. General methods of preparation have been examined, based on the three following reagents: (a) hydrogen fluoride + N-bromoacetamide; (b) diethyl monofluoromalonate; and (c) perchloryl fluoride. The first of these is the recommended procedure for simple unsubstituted α-fluoro acids; however, the fluoromalonate route is less vigorous, and is therefore the method of choice for those α-fluoro acids that contain labile functional groups.

Host resistance to the fir engraver beetle. 1. Monoterpene composition of Abies grandis pitch blisters and fungus-infected wounds

1976 ◽  
Vol 54 (1-2) ◽  
pp. 14-18 ◽  
Author(s):  
Charles E. Russell ◽  
Alan A. Berryman
Keyword(s):  
Gas Chromatography ◽  
Host Resistance ◽  
Bark Beetles ◽  
Biologically Active ◽  
Bornyl Acetate ◽  
Resin System ◽  
Fungus Infection ◽  
Abies Grandis ◽  
Infected Wounds ◽  
Monoterpene Composition

The monoterpene hydrocarbons of the cortical blister oleoresin of Abies grandis were compared, using gas chromatography, with those obtained from lesions that formed as a response of the tree to inoculation with cultured Trichosporium symbioticum, a fungus which is transmitted by the fir engraver beetle Scolytus ventralis. The resins from each source differed both quantitatively and qualitatively. Three terpenic compounds (tricyclene, camphene, and bornyl acetate) that are normally present in primary resin were not found in secondary resin. However, resins that formed in response to the inoculation contained higher concentrations of myrcene in three quarters of the trees and delta3-carene in one quarter of the trees that were sampled than resin from pitch blisters, which contained only trace amounts of these two compounds. These results suggest that conifers respond to fungus infection by producing monoterpenes which are more toxic, repellent, and (or) inhibitory to bark beetles and their associated fungi (e.g. myrcene and delta3-carene) at the expense of attractive or less biologically active compounds (e.g. camphene) which are present in the preformed resin system.

Cyclic nitrones. II. Reactions of a cyclic α-keto nitrone with acetic anhydride, acetone, and methyl acetoacetate

1967 ◽  
Vol 20 (11) ◽  
pp. 2485 ◽  
Author(s):  
RFC Brown ◽  
WD Crow ◽  
L Subrahmanyan ◽  
CS Barnes
Keyword(s):  
Acetic Anhydride ◽  
Sulphuric Acid ◽  
Functional Groups ◽  
Potassium Hydroxide ◽  
Methyl Acetoacetate ◽  
Cyclic Nitrones ◽  
Aqueous Potassium Hydroxide ◽  
Isopropenyl Acetate

The cyclic α-keto nitrone 3,4,5,6-tetrahydro-5,5-dimethyl-3-oxopyridine 1-oxide (III) when treated with acetic anhydride and sulphuric acid gave in low yield a compound (XI) having both enol lactone and vinylogous amide functional groups. Hydrolysis and decarboxylation of compound (XI) with aqueous potassium hydroxide gave a vinylogous amide (V), also obtained by acid- or base-catalysed condensation of compound (III) with isopropenyl acetate or acetone. Base-catalysed condensation of (III) with methyl acetoacetate gave an ester (XVII) closely related to compound (V).

SYNTHESIS OF 2-, AND 3-NITROBENZANTHRONE VIA DIRECT NITRATION OF BENZANTHRONE WITH NITRIC ACID/ACETIC ACID

2019 ◽  
Vol 71 (1) ◽  
Author(s):  
Kefa K. Onchoke ◽  
Jorge J. Ojeda
Keyword(s):  
Acetic Acid ◽  
Nitric Acid ◽  
Acetic Anhydride ◽  
Standard Sample ◽  
Major Product ◽  
Fragmentation Patterns

Abstract Three mono-nitrobenzanthrone isomers (1-, 2-, and 3-nitrobenzanthrone; 1-, 2-, and 3-NBA) were synthesized by reacting benzanthrone (BA) with nitric acid (HNO3) in acetic anhydride at ice-cold conditions. The major product, 2-nitrobenzanthrone (2-NBA), was confirmed using GC-MS via comparisons with a standard sample. On the basis of the elution profiles and fragmentation patterns two other isomers formed were assigned to 1-, and 3-nitrobenzanthrone (1-, and 3-NBA). The average percent yields of 1-, 2-, and 3-NBA were 0.3 ± 0.1%, 10.5 ± 2.6 %, and 6.4 ± 1.3 %, respectively.

Hypervalent Iodine-mediated/Catalyzed Oxidative Cycloisomerization/Annulation of Alkynes for Metal-free Synthesis of Oxazoles

2020 ◽  
Vol 24 (18) ◽  
pp. 2048-2069
Author(s):  
Akio Saito
Keyword(s):  
Functional Groups ◽  
Single Step ◽  
Biologically Active ◽  
Hypervalent Iodine ◽  
Sustainable Chemistry ◽  
Metal Free ◽  
Triple Bonds ◽  
Iodine Species ◽  
Low Toxicity ◽  
Synthetic Intermediates

Since oxazoles have found widespread applications not only as synthetic intermediates but also as biologically active compounds, much effort has been focused on developing novel and efficient methods for the synthesis of this heterocycle. From the viewpoint of green and sustainable chemistry, hypervalent iodine and other halogen reagents have gained increasing popularity in metal-free oxidative transformation due to their low toxicity, transition-metal-like reactivity, high stability, easy handling and other benefits. In this account, our two approaches to the metal-free synthesis of oxazoles by means of a peculiar activation of alkynes by iodine species are described with the related contexts. One is iodine(III)-mediated/catalyzed oxidative cycloisomerization reactions of N-propargyl amides for the preparation of oxazoles bearing various functional groups at their side chains. In these reactions, iodine(III) species works as a donor of various heteroatomic functional groups as well as an activator of carbon-carbon triple bonds in a single step. Furthermore, this methodology can be extended to iodine(III)-mediated/catalyzed oxidative annulation of alkynes and nitriles as another approach, in which heteroatoms on iodine(III) species are incorporated in the azole rings.

Sign in / Sign up

Export Citation Format

Share Document