Reference

Laxative sennoside isolation

Laxative sennoside isolation. Ohshio, Haruji; Imahori, Masahiko (Takeda Chemical Industries, Ltd., Japan). Japan. Kokai JP 52139712 21 Nov 1977 Showa, 3 pp. (Japanese). (Japan). CODEN: JKXXAF. CLASS: IC: A61K031-70. APPLICATION: JP 76-56788 17 May 1976. DOCUMENT TYPE: Patent CA Section: 63 (Pharmaceuticals) Laxative sennosides are obtained by pptn. of the compds. from sennoside-contg. solns. with Pb salts and the Pb salts are removed by converting them to PbSO4 or Pb halides. Thus, powd. Rheum palmatum was extd. with 50% MeOH solns. and filtered, and the ext. was treated with Pb(OAc)2 to give a ppt., which was repeatedly washed with 50% MeOH solns. The ppt. was treated with 10% Na2SO4 followed by MeOH. The sol. fraction was concd. and the resultant product was extd. with 90% MeOH and filtered. The filtrate was concd. to give yellow or brown powder contg. sennosides A [81-27-6], B [128-57-4], C [37271-16-2], D [37271-17-3], E [11137-63-6], and F [52842-23-6] and their derivs.

Purification of sennosides

Purification of sennosides. Ogawa, Shntaro; Yoshida, Akiyoshi; Kato, Reiko (Rohto Pharmaceutical Co., Ltd., Japan). Japan. Kokai JP 52054012 2 May 1977 Showa, 3 pp. (Japanese). (Japan). CODEN: JKXXAF. CLASS: IC: A61K031-70. APPLICATION: JP 75-128188 23 Oct 1975. DOCUMENT TYPE: Patent CA Section: 63 (Pharmaceuticals) Medicinal compns. contg. sennosides are isolated and purified by ion-exchange column chromatog. to prevent side effects. Thus, exts. contg. sennoside Ca salts dissolved in H2O were chromatographed on DEA cellulose columns, and eluted with 0.1M NaCl to give monoanthraquinone derivs., with 0.2M to give sennoside D (I) [37271-17-3] and sennoside B [128-57-4], and with 0.3M to give sennoside A [81-27-6]. A and B were concd. and pptd. with dild. HCl at pH 1-2 and D at pH 3-3.5. The ppts. were filtered and washed to give crude crystals, and were recrystd. 1-3 times with 70g acetone to give pure cryst. sennosides A, B, and D.