Learn More
The discovery of antiprogestational steroids by the Roussel-Uclaf group not only was a major scientific advance but also opened the way to new methods of fertility control and new therapies for such conditions as cancer. RU486, the prototype of the series, is distinguished by a p-(N,N-dimethylaminophenyl) substituent at the 11 beta- position of the steroid(More)
The cross-axis synchronous flow-through coil planet centrifuge with a 20-cm revolutional radius and a total capacity of 1600 ml was successfully applied to preparative counter-current chromatography of various biological samples, which include sea buckthorn extract, steroid reaction mixture, indole plant hormones, and dinitrophenylamino acids. The present(More)
16 alpha-Ethyl-17 beta-acetyl substitution in the D-ring of steroids having an 11 beta-aryl-4,9-dien-3-one structure resulted in compounds with strong progestational activity. These compounds caused endometrial proliferation in the uterus of estrogen-primed rabbits with a potency greater than that of progesterone and had no detectable antiprogestational(More)
The semipreparative capability of the newly developed high-speed counter-current chromatograph equipped with a set of three multilayer coils has been demonstrated in separations of a variety of biological samples including triterpenoic acids, indole auxins, bacitracin, flavonoids and tetracycline derivatives, each with a suitable two-phase solvent system.(More)
A number of mono- and bicyclic endoperoxides were prepared and tested for antimalarial activity in search of a simplified analogue of the 5-oxygen-substituted 1,2,4-trioxane ring structure of the naturally occurring antimalarial qinghaosu. The compounds were assayed in an in vitro system for antimalarial activity against chloroquine-susceptible and(More)
Analogs of (4aRS,5SR,9bRS)-2-ethyl-2,3,4,4a,5,9b-hexahydro-7-meth yl-5-p- tolyl-1H-indeno[1,2-c]pyridine (Sandoz 20-438, 10a; R1 = ethyl, R2 = R3 = methyl, R4 = H) have been synthesized and tested in mice for their ability to reduce testes weight and disrupt spermatogenesis. The activity was strongly dependent on stereoisomerism and chirality, consistent(More)
Technical chlordane, as manufactured in the U.S.A. since 1950, is claimed to be a uniform producty However, its composition is different from earlier preparations (1) and the published literature gives little information about the chemical nature of the various components. In 1952, March (2) isolated chlordenes heptachlor and two isomers of chlordane(More)
The versatility and 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 that integrates the advantages of countercurrent chromatography with the low(More)