Some unreported by-products from the reaction of 1,4-dien-3-one steroids with 2-(methylammo)benzethiol/BF3.
In a previous report, it was demonstrated that the 3-carbonyl of androsta-1,4-dien-3,17-dione (ADD) can be selectively protected with 2-(methylamino)benzethiol in the presence of BF3 in good yield. We explored the applicability of this method for other 1,4-dien-3-one steroids and got the desired protective products in different yield. Other than the usual protected products, we also got some unexpected by-products, including benzathiazol[4,3-b]-estra steroids. Their structures were determined by spectral analysis.
Zhang
Bei Na
BN
Department of Medicinal Chemistry, The School of Pharmacy, Fudan University, Shanghai 200032, China.
Chen
Ying
Y
Zhang
Qian
Q
Xia
Peng
P
D001880:Boranes / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D013256:Steroids / Q000138:chemical synthesis / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D014961:X-Ray Diffraction
D001880:Boranes; D013256:Steroids; D013438:Sulfhydryl Compounds; C021274:boron trifluoride