3,17.alpha.-dihydroxy-5,6-dichloro-20-keto-pregnane

3,19-disubstituted 5-androstenes

3,20 dioxo-17-methyl 19 nor pregna-4,9,11-triene

3,20-acyloxy pregnane derivatives

3,20-diketo-11.alpha.-hydroxypregnane production

3,20-dioxo 16.alpha.,17.alpha.-dihydroxy 19-nor pregna-4-ene

3,20-dioxo 19-nor 4,9,11-pregnatriene et procede de preparation

3,3',5,5'-tetraalkyldiphenoquinones

3,3'-biisoxazole

3,3'-bis-(1-substituted-2,5-diketo-7-methyl-pyrimidopyrazoles)

3,3'-bis-2-pyrazolines

3,3'-bis-4-hydroxycoumarinylacetone

3,3'-dinitro-octofluorobiphenyl and a process for preparing it

3,3'-dithiobis(3-azabicyclo(3.2.2)nonane)

3,3'-ethylenebis(tetrahydro-4,6-dimethyl-2h-1,3,5-thiadiazin...

3,3'-iminobispropylurea

3,3'-methylene-bisthiazolidine

3,3,3-nitrilotrispropanamide

3,3,3-trichloro-1,1,2,2-tetrafluoropropane

3,3,3-trichloro-1,2-propanediol