Reference

Polyurethane elastomers

Polyurethane elastomers. (Mitsubishi Gas Chemical Co., Inc., Japan). Jpn. Kokai Tokkyo Koho JP 58194914 A2 14 Nov 1983 Showa, 3 pp. (Japanese). (Japan). CODEN: JKXXAF. CLASS: IC: C08G018-32. APPLICATION: JP 82-77990 10 May 1982. DOCUMENT TYPE: Patent CA Section: 39 (Synthetic Elastomers and Natural Rubber) Polyurethane elastomers prepd. by curing ann isocyanate-terminated prepolymer with 1,3-xylylene glycol (I) [626-18-6] have excellent workability and exhibit excellent mech. and heat resistances. Thus, 100 parts Adeka P-100 (polypropylene glycol) and 50 parts MDI were mixed 3 h at 80° to give a urethane prepolymer which was heated at 80-100°, defoamed in a vacuum, and mixed with 9 parts I. The mixt. was molded and cured to give a polyurethane [90999-05-6] elastomer with excellent tensile strength.

Multivalent Templated Saccharides: Convenient Syntheses of Spacer-Linked 1,1'-Bis -and 1,1',1''-Tris-b-glycosides by the Glycal Epoxide Glycosidation Method

Multivalent Templated Saccharides: Convenient Syntheses of Spacer-Linked 1,1'-Bis -and 1,1',1''-Tris-b-glycosides by the Glycal Epoxide Glycosidation Method. Patch, Raymond J.; Chen, Hang; Pandit, Chennagiri R. (Department of Rational Drug Design, Procept Inc., Cambridge, MA 02139, USA). Journal of Organic Chemistry, 62(5), 1543-1546 (English) 1997 American Chemical Society. CODEN: JOCEAH. ISSN: 0022-3263. DOCUMENT TYPE: Journal CA Section: 33 (Carbohydrates) Complex carbohydrates present on glycoproteins and glycolipids mediate a wide range of biol. responses in organisms including cellular recognition, adhesion and proliferation. 626-18-6 and 188010-99-3 which are cas registry numbers are also used here. Their syntheses still pose formidable synthetic challenges from a drug development standpoint. Towards this end, we report that Danishefsky's glycal epoxide glycosidation methodol. extends to the prepn. of bis- and tris-b-glycosides in good yields in a single step. Thus, reaction of glycal epoxides with primary diols and triols affords scaffold linked bis- and tris-glycosides I (R = Q) with the high b-selectivity obsd. in the previously reported monoglycosidation reactions. This methodol. should be of practical utility in the development of therapeutically important oligosaccharide mimics of complex carbohydrates. .