| 摘要 |
<p>Crystalline gamma-bestatin (I) with the following X-ray pattern is new: d (A) 27.59, 13.80, 6.86, 5.57, 5.47, 5.09, 4.79, 4.55, 4.41, 3.78, 3.43 and the corresp. I/I, 0.23, 1.00, 0.08, 0.03, 0.03, 0.02, 0.02, 0.28, 0.03, 0.03, 0.03, 0.04. - (I) can be prepd. by (a) heating hygroscopic bestatin crystals and/or the corresp. hydrate to 148 deg. C to the m.pt. of bestatin or (b) by suspending or kneading hygroscopic bestatin crystals and/or the corresp. hydrate in one or more organic solvents, chosen from acetone, methylethylketone, diethylketone, THF, ethylacetate, dioxan, isopropyl alcohol or aq. MeOH. - Bestatin is a substance of very low toxicity which can be isolated from streptomyces olivoreticuli and used as an inhibitor for aminopeptidase and to increase the immunity reaction, activate the body's defence mechanisms and thus inhibit cancerous growths. (I) is non-hygroscopic, contains no water of crystallisation and is stable in such amts. that there is no mass change when subjected to very damp conditions or heat. (I) can therefore be easily used in the prepn. of pharmaceuticals contg. bestatin. DEAB- DE3246135 C Crystalline gamma-bestatin (I) with the following X-ray pattern is new: d (A) 27.59, 13.80, 6.86, 5.57, 5.47, 5.09, 4.79, 4.55, 4.41, 3.78, 3.43 and the corresp. I/I, 0.23, 1.00, 0.08, 0.03, 0.03, 0.02, 0.02, 0.28, 0.03, 0.03, 0.03, 0.04. - (I) can be prepd. by (a) heating hygroscopic bestatin crystals and/or the corresp. hydrate to 148 deg. C to the m.pt. of bestatin or (b) by suspending or kneading hygroscopic bestatin crystals and/or the corresp. hydrate in one or more organic solvents, chosen from acetone, methylethylketone, diethylketone, THF, ethylacetate, dioxan, isopropyl alcohol or aq. MeOH. - Bestatin is a substance of very low toxicity which can be isolated from streptomyces olivoreticuli and used as an inhibitor for aminopeptidase and to increase the immunity reaction, activate the body's defence mechanisms and thus inhibit cancerous growths. (I) is non-hygroscopic, contains no water of crystallisation and is stable in such amts. that there is no mass change when subjected to very damp conditions or heat. (I) can therefore be easily used in the prepn. of pharmaceuticals contg. bestatin. (Dwg.0/2) GBAB- GB2111991 B Bestatin in the form of gamma-form crystals, said crystals having an X-ray diffraction pattern as shown in the following Table A; d (Angstrom) I/I1, 27.59, 0.20; 13.80, 1.00; 6.86, 0.08; 5.57, 0.03; 5.47, 0.03; 5.09, 0.02; 4.79, 0.02; 4.55, 0.28; 4.41, 0.03; 3.78, 0.03; 3.43, 0.04.e USAB- US4769490 A Prepn. of gamma crystalline bestatin comprises heating hygroscopic bestsin or hydrate at 148 deg.C-M.Pt. (150-200 deg.C) for 1+ hr. or by suspending or kneading in acetone MeEt ketone, Et2 ketone, THF, EtAc, dioxane, iPrOH, aq. MeOH or mixt. for 10+ (20-280) mins.</p> |
