摘要:
A novel cyclic acetal derivative of sucrose, 4,6-O-isopropylidenesucrose, is prepared by treating sucrose with 2,2-dimethoxypropane in N,N-dimethylformamide, in the presence of p-toluenesulphonic acid, suitably at room temperature. The product is conveniently isolated in the form of its hexa-acetate or hexabenzoate, by treatment with acetic anhydride or benzoyl chloride, respectively, in pyridine. The resulting compounds are valuable as synthetic intermediates and in conformational investigations.
摘要:
The novel chlorinated sugar O-.alpha.-D-6-chloro-6-deoxygalactopyranosyl-(1.fwdarw.6)-.alpha.-D-4-chloro-4-deoxygalactopyranosyl-(1.fwdarw.2)-.beta.-D-1, 6-dichloro-1, 6-dideoxyfructofuranoside (TCR) can be used to prepare sucralose by incubating the TCR in solution in the presence of an enzyme serving to remove the 6-chloro-6-deoxygalactosyl moiety from the 6-position, especially an enzyme derived from a strain of Mortierella vinacea, Circinella muscae or Aspergillus niger. TCR is prepared by treating raffinose with thionyl chloride in the presence of triphenylphosphine oxide.
摘要:
A process for the preparation of 4,1',6'-trichloro-4,1',6'-trideoxygalactosucrose (TGS) comprising the steps of:(a) reacting sucrose with an acylating reagent under conditions to provide a mixture of acylated sucrose derivatives containing a major proportion of 6-monoacylated material;(b) optionally separating 6-monoacylated sucrose derivative from other acylated derivatives before step (c);(c) reacting the monoacylated sucrose derivative with a chlorinating reagent capable of chlorinating at positions 1', 4 and 6' of a sucrose 6- acylate; and(d) deacylating and separating (in either order) the 4,1',6'-trichloro-4,1',6'-trideoxygalactosucrose material formed.
摘要:
Compounds of the general formula: ##STR1## (in which X represents a hydrogen atom or an alkoxy or arylalkoxy group) are new compounds; those where X represents a hydrogen atom or a methoxy group are potent sweeteners while those with a cleavable 6-ether group are key intermediates in the preparation of 4,1',6'-trichloro-4,1',6'-trideoxygalactosucrose (TGS). They are prepared by chlorinating a sucrose 6-ether, by etherifying a suitably protected derivative of TGS or, in the case where X represents hydrogen, by debromination of 6-bromo-4,1',6'-trichloro-4,6,1',6'-tetradeoxygalactosucrose.
摘要:
A process for the chlorination of sucrose or a derivative thereof, comprises reaction of the sucrose or derivative thereof with thionyl chloride and a nitrogen base at a ratio of about 1 molar equivalent (ME) of thionyl chloride and about 1 ME of base for every ME of free hydroxyl, in a non-reactive moderately polar solvent. The process is particularly suitable for the preparation of sucralose.
摘要:
A method of sweetening a substance comprises incorporating therein a mono- or poly- chloro, mono- or poly- deoxy sucrose derivative having chlorine atoms in selected combinations of positions 4,6,1'- and 6'- of the sucrose molecule. The compounds are many times sweeter than sucrose and are formulated as ingestible products, such as foodstuffs and beverages; oral compositions, such as toothpaste and chewing gum; or sweetening compositions, such as tablets, for addition to beverages, etc.
摘要:
Resins for use in making resin-coated granules are made by preparing a novolak resin from a phenol and formaldehyde in the presence of lactose and/or galactose, using an acid catalyst. Melt-coating the resin with an amine curing agent on to particulate refractory material gives resin-coated granules which can be moulded to make foundry moulds. The lactose and/or galactose can replace part of the phenol conventionally employed in preparing novolak resins and avoids the need for plasticizers.
摘要:
Sucrose or derivatives thereof such as esters are acylated at the 4'- and/or the 6- position by reaction with a donor acyl ester, e.g. a reactive ester of an alkanoic acid or benzoic acid, in the presence of lipase. Sucrose 6,4' so produced can be chlorinated and deacylated to produce the sweetener sucralose.
摘要:
Compounds of the general formula (I) are potent sweeteners, especially 4,1',6'-tribromo-4,1',6'-trideoxygalactosucrose: ##STR1## in which R' represents a chlorine or bromine atom;R.sup.2 and R.sup.3 respectively represent a hydroxy group and a hydrogen atom or a hydrogen atom and a chlorine or bromine atom;R.sup.4 represents a chlorine or bromine atom; at least one of R', R.sup.3 and R.sup.4 representing a bromine atom.
摘要:
A method of sweetening a substance comprises incorporating therein a mono- or poly- chloro, mono- or poly- deoxy sucrose derivative having chlorine atoms in selected combinations of positions 4,6,1'- and 6'- of the sucrose molecule. The compounds are many times sweeter than sucrose and are formulated as ingestible products, such as foodstuffs and beverages; oral compositions, such as toothpaste and chewing gum; or sweetening compositions, such as tablets, for addition to beverages, etc.