| 摘要 |
545,360. Ribonyl derivatives. PFIZER & CO., C. Nov. 20, 1940, No. 16712. Convention date, Dec. 16, 1939. [Class 2 (iii)] Tetra-acylated ribonyl derivatives including tetra-acylated ribose in the aldehyde form are prepared by tetra-acylating ribonamide, treating this with nitrous anhydride to form tetraacylated ribonic acid, forming the acid chloride, and finally reducing to the free aldehyde ribose. The d-ribonaniide which forms the starting material for the series of reactions is preferably prepared by treating d-ribonolactone in alcohol solution with dry ammonia. In an example d-ribonamide is treated with acetic anhydride in pyridine solution to form tetra-acetyl-dribonamide which is then dissolved in glacial acetic acid or treated with the gas obtained by reacting sodium nitrite with excess of sulphuric acid. On removing the acetic acid, tetraacetyl-d-ribonic acid is isolated. The corresponding acid chloride which is obtained by reaction with phosphorus pentachloride in chloroform solution, is then reduced by hydrogen in the presence of a Pd-Ba SO catalyst in xylene solution to form tetra-acetyl-d-ribose. |
