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H N Elsohly

Publications and source records attributed to H N Elsohly.

9 recordsLinked to original sources
PubMed1984

Local anesthetic effects of cocaine and several extracts of the coca leaf (E. coca).

Cocaine and a number of different fractions of a crude ethanol extract of the coca leaf (E. coca) were subjected to a local anesthetic screen using rat tail withdrawal from electric shock. Following an intradermal injection of 0.1 ml of a 2.0% (w.v) solution of cocaine HCl, an immediate response was observed. Two of the coca fractions also produced some local anesthesia. An alkaloidal fraction, containing an equivalent amount of cocaine, produced a maximum effect that was approximately 20% less than that observed with cocaine. The only other fraction producing any effect, a water soluble cocaine-free fraction, showed a maximum response that was approximately 30% of that observed with cocaine.

Anesthetics, Local↗
PubMed1982

Comparative lethality of coca and cocaine.

The 24 hour lethal effects of cocaine were compared to those of a crude ethanol extract of the coca leaf (Erthroxylon coca) in male, Swiss mice. Various doses of cocaine HCl and coca leaf extracts suspended in a Tween 60, Arlacel 83, and distilled water vehicle were injected IP into groups of 10 mice. The LD50 for cocaine was 95.1 mg/kg. The LD50 for the coca extract was 3450 mg/kg. The LD50 of the extract based on its cocaine content was 31.4 mg/kg. The results clearly indicate that the coca leaf contains constituents other than cocaine that can contribute to a toxic effect of the plant.

Animals↗
PubMed1981

Comparative stimulus properties of two fractions of the coca leaf (E. coca).

Male and female Wistar rats were trained to discriminate 5.0 mg/kg cocaine from 2.0 ml/kg saline using a two-bar food reinforcement (FR 30) drug discrimination paradigm. Once discrimination behavior had stabilized the subjects were tested (in extinction) with several doses of two different fractions of the coca leaf and four doses of cocaine HCl (1.0, 2.5, 7.5, 10 mg/kg). The fractions were prepared by extracting powdered coca leaves with 95% ethanol and then partitioning the residue between chloroform and water. Two doses of the water fractions (480, 960 mg/kg) and five doses of the chloroform fraction (7.5, 15, 30, 60 120 mg/kg) were tested. The water fractions was devoid of cocaine while the five doses of the chloroform fraction contained cocaine equivalent to 0.4, 0.83, 1.65, 3.3 and 6.6 mg/kg, respectively, as determined by gas chromatographic analysis. The 2.5, 7.5, and 10.0 mg/kg cocaine doses generalized to cocaine. The 1.0 mg/kg dose of cocaine generalized to saline. The water fraction at 480 mg/kg generalized to saline; however following pretreatment with the 960 mg/kg dose of this fraction, the animals failed to respond. The two largest doses of the chloroform fraction (60 and 120 mg/kg) generalized to cocaine while the other three doses did not. The 7.5 mg/kg generalized to saline; the 15 and 30 mg/kg doses engendered an intermediate level of responding on both the cocaine and saline lever.

Animals↗
PubMedDate not supplied

Microbial transformation studies on arteannuin B.

The microbial transformation of the sesquiterpene lactone arreannuin B [3] using Aspergillus flavipes produced dihydroarteannuin B [4] as the main transformation product. Preparative-scale fermentation of 3 with Beauveria bassiana, on the other hand, has resulted in the production of two metabolites, 3 beta-hydroxyarteannuin B [5] and 13-hydroxy-11-epi-dihydroarteannuin B [6]. The structure of these metabolites, all of which are new compounds, was established using chemical and spectroscopic techniques. The isomeric dihydrocompound, 11-epi-dihydroarteannuin B [7] and an isomer of arteannuin B [8] were also prepared chemically. All compounds were subjected to 2D-nmr experiments and full 1H- and 13C-nmr assignments were made.

Artemisinins↗
PubMedDate not supplied

Constituents of Cannabis sativa L. XXII: isolation of spiro-indan and dihydrostilbene compounds from a Panamanian variant grown in Mississippi, United States of America.

Three spiro-compounds, namely cannabispiran, dehydrocannabispiran and beta-cannabispiranol, and 2 dihydrostilbenes [3-(2-(3-hydroxy-4-methoxyphenyl)ethyl)-5-methoxyphenol and canniprene] were isolated from a polar fraction of a Panamanian variant of Cannabis sativa L. grown in Mississippi, United States of America. The plant material was extracted with 95% ethanol and the dried ethanol extract was then partitioned between chloroform and water. The chloroform fraction was fractionated between hexane and 3N sodium hydroxide solution. Acidification of the basic fraction followed by extraction with ether afforded a polar acidic fraction from which the above-mentioned compounds were isolated through repeated chromatography. The structures of the above compounds were determined by spectral means as well as by comparison with reference samples. The isolation of two dihydrostilbenes and three spiro-indan compounds from a single variant provides good support that the dihydrostilbenes are the natural precursors to the spiro-indan compounds.

Cannabis↗