Clarence Cook

Germination of Witchweed (Striga lutea Lour.): Isolation and Properties of a Potent Stimulant.

A crystalline germination stimulant (trivial name strigol) for the rootparasite, witchweed (Striga lutea Lour.), has been isolated from cotton rootexudates and characterized as a C19H22O6 compound. Although apparently different from known plant hormones, the stimulant is active at hormonal levels, causing germination at concentrations less than 1O-5 part per million.

Dual Countercurrent Chromatography

Abstract A modern method of performing conventional countercurrent distribution called Dual Countercurrent Chromatography is described. The system consists of a multilayer coiled column integrated with two inlet and two outlet lines for solvent phases and a sample feed line. Subjecting the system to a particular combination of centrifugal and planetary motions produces a unique hydrodynamic effect which allows two immiscible liquids to flow countercurrently through the coiled column. The sample solution is fed at the middle portion of the column and eluted simultaneously through the column in the opposite direction by two liquids. This distinct feature of maintaining a constant fresh two phases within the coiled column permits a rich domain of application, such as continuous sample process and continuous extraction. The present paper describes the application of this dual countercurrent system to the separation of natural products and synthetic intermediates. Preliminary results indicate that this new met...

Application of Countercurrent Chromatography/Thermospray Mass Spectrometry for the Analysis of Natural Products

Abstract The versatility and high resolving power of countercurrent chromatography (CCC) has been demonstrated with a newly developed analytical high speed planet centrifuge system. Interfacing countercurrent chromatography with mass spectrometry (MS) provides a new analytical methodology which integrates the advantages of countercurrent chromatography with the low detection limit and identification capability of mass spectrometry. The capability of thermospray CCC/MS is evidenced in a preliminary study of plant alkaloids. The technique proved useful in identifying an unknown impurity and in validating the presence of a specific compound in a mixture. The thermospray CCC/MS can become a useful and complementary method to thermospray HPLC/MS for the analysis of nonvolatile or thermally unstable molecules.

THE USE OF MARIHUANA, ETHANOL, AND OTHER DRUGS AMONG DRIVERS KILLED IN SINGLE-VEHICLE CRASHES

Marihuana, ethanol, and other drugs are considered by many to be detrimental to the safe operation of motor vehicles. However, direct epidemiological evidence for this belief exists only for ethanol. The goal of this investigation was to determine the incidence of the psychoactive ingredient of marihuana, Δ9-tetrahydrocannabinol (THC), along with ethanol and other drugs in blood specimens from a carefully defined population of dead drivers. Although THC and other drugs were present in a small number of the blood specimens, the large number of specimens that had high blood ethanol concentrations indicated that alcohol is still the major drug affecting highway safety.

Evaluation of a 1-year levonorgestrel-releasing contraceptive implant: side effects, release rates, and biodegradability

Objective To determine the release rates, effects on ovulation, and side effects of two lengths of a biodegradable, subdermal contraceptive implant containing levonorgestrel in a caprolactone capsule. Design Phase II randomized clinical trial. Setting Public family planning clinic at an urban general hospital. Participants Forty-eight healthy, parous, ovulating volunteers. Intervention Subjects were randomly assigned either a 2.5- or a 4.0-cm contraceptive capsule that was worn under the skin of the upper arm for 1 year if not removed earlier for other reasons. Main Outcome Measures Serum concentrations of levonorgestrel, progesterone, estradiol, and lipoproteins were measured as were metabolic parameters. Vaginal bleeding and other side effects were recorded. After implant removal, remaining levonorgestrel, capsule viscosity, and molecular weight were measured. Results The 4-cm implant provided serum concentrations of levonorgestrel ranging from 0.65ng/mL shortly after insertion to 0.20ng/mL at 12 months, but the 2.5-cm implant resulted in levels too low for contraception. The 4-cm implant suppressed ovulation in approximately 80% of cycles over 1 year of use, but the 2.5-cm implant failed to suppress ovulation. The implants were rapidly and easily inserted and removed. They retained structural integrity through 1 year of use. Of 48 subjects, 32 had abnormal bleeding patterns; the mean number of days of bleeding per month was 7 with 23 days between episodes. Women using capronor maintained normal metabolic parameters except that low-density lipoprotein decreased slightly. Conclusions The 4.0-cm implant is a promising contraceptive. There were no important metabolic effects, but there were bothersome minor side effects typical of progestin-only contraception.

A novel silver-sulfoethyl cellulose column for purification of ethynyl steroids from biological fluids

Abstract A method for purification of ethynyl steroids from biological fluids has been developed using silver-sulfoethyl cellulose column chromatography. Ethynyl steroids were applied in methanol, and the firm binding allowed the columns to be washed with methanol, ethyl acetate, or diethyl ether to remove endogenous materials. Nonethynylated steroids did not bind to silver-sulfoethyl cellulose. Release of ethynylated steroids was achieved with a saturated NaCl/methanol solution. Dehydration or de-ethynylation of ethynyl estradiol, ethynodiol diacetate, and ethynodiol was not observed. The utility of this technique for purification of ethynyl steroid metabolites from the urine of a beagle metabolizing norethynodrel was demonstrated.

Analytical High Speed Countercurrent Chromatography

Abstract The resolution of countercurrent distribution has long been demonstrated. However, the long elution time limits its analytical applications. The development of a high speed planet centrifuge has markedly improved the efficiency of the system; thus the countercurrent chromatography can be completed within several hours instead of days. Further reduction in separation time is still needed for analytical use, however. The most effective approach to improve the efficiency is to use a smaller diameter tubing for the multilayer coiled column, because it provides for better phase mixing. Under standard operation conditions, the increased phase interaction has resulted in steady carry-over of the stationary phase. This was solved with a high revolutional speed which provides the necessary centrifugal force for sustaining the stationary phase. Excellent phase retention and resolution have been achieved with a 0.85 mm i.d. column and a 2000 rpm revolutional speed. The analytical capability of the new syste...

28-day toxicology test: indenopyridine RTI 4587-056 in male Sprague-Dawley rats.

The potential toxicity of RTI 4587-056, a hexahydroindenopyridine analog of SANDOZ 20-438, was examined in adult male Sprague-Dawley rats. Testicular, intestinal, and erythropoietic histology was assessed after 28 days of gavage treatment at 0, 10, and 100 mg/kg/day. During the first 10 days, dose-related clinical signs included mild to moderate lethargy shortly after dosing, lower consumption of feed and water, and body weight loss or decreased weight gain. Tolerance developed, such that lethargy disappeared and weight gains were equivalent to the control group during the second through fourth weeks. The compound did not affect intestinal epithelium or bone marrow. RTI 4587-056 was a highly effective antispermatogenic agent at both doses causing epididymal hypospermia and testicular atrophy. Based upon the Spermatogenic Index ratings, still lower doses would be effective male contraceptive agents. RTI 4587-056 has potential as a male contraceptive without overt side effects. Further testing is required.

Metabolism of norethynodrel by rat liver

The incubation in vitro of norethynodrel with the postmitochondrial supernatant from rat liver results in the formation of three intermediary metabolites, namely the 3α- and 3β-hydroxy derivatives and norethindrone. These three steroids are further metabolized to more polar compounds thought to be polyhydroxylated end-products. Incubation of the polar products with glucuronidase and sulfatase suggests that these compounds exist as free steroids rather than as conjugates.

The preparation of 3α- and 3β, 17β-dihydroxy-17α-ethynyl-estr-5(10)-ene 1

Abstract Norethynodrel (1, 17β-hydroxy-17α-ethynyl-estr-4-en-3-one) when reduced at -70°C with lithium tri(t-butoxy) hydride yielded predominantly (98%) the equatorial Sec-alcohol II together with 27. of the axial 3β-alcohol III. Reduction of norethynodrel with sodium borohydride resulted in increased yields of the 3β alcohol III, the ratio of the 3α to 3β-alcohols varying from 4:1 to 3:1 depending upon the solvent used. The 3β-aicohol III was obtained in 38% yield following reduction of the ketone I with diisobutylaluminum hydride. The most efficient synthesis of the 3β-alcohol III was by a MeerweinPondorff reduction of ketone I carried out over a very short reaction period (9). In an alternate route the equatorial 3α-alcohol II was converted to the 3β-axial alcohol III via the 3α-mesitylenesulfonyloxy derivatives IVd and the 3β formate V.