The present invention provides N-acetyl derivatives of sialic acids, including N-acetyl derivatives of Neu5Ac and Neu5Gc. Methods for preparing related precursors and a variety of sialosides are also disclosed.

Compounds of Formula (A) are described herein and the uses thereof for the treatment of diseases, conditions and/or disorders mediated by pharmaceutical compositions and the uses thereof as asialoglycoprotein receptor (ASGPR) targeting agents.

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Compounds of Formula (A) are described herein and the uses thereof for the treatment of diseases, conditions and/or disorders mediated by pharmaceutical compositions and the uses thereof as asialoglycoprotein receptor (ASGPR) targeting agents.

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The present invention relates to compounds of formula (I) and compositions comprising them for use in enhancing umami taste and/or saltiness of a food product.

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The present invention relates to compounds of formula (I) and compositions comprising them for use in enhancing umami taste and/or saltiness of a food product.

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The present invention relates to compounds and compositions for use in enhancing flavor and/or saltiness of a food product. Particularly, the present invention relates to compounds of the general formula I) and compositions comprising them.

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The present invention relates to compounds and compositions for use in enhancing flavor and/or saltiness of a food product. Particularly, the present invention relates to compounds of the general formula I) and compositions comprising them.

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Disclosed herein a sialyl donor and its use for the synthesis of gangliosides. The sialyl donor has the structure of, ##STR00001##
wherein, R.sub.1 and R.sub.2 are independently benzoyl, toluenesulfonyl, pivaloyl or acetyl optionally substituted with a halogen; and R.sub.3 is acetyl or (O)CCH.sub.2OH. In one preferred embodiment, in the sialyl donor of formula (I), R is acetyl. Also disclosed herein is a method of synthesizing a sialoside. The method comprises steps of: coupling the sialyl donor of formula (I) with a glycosyl acceptor having a primary hydroxyl group in the presence of N-iodosuccinimide (NIS) and trifluoromethanesulfonic acid (TfOH) under suitable conditions; and isolating the sialoside, which has an -glycosidic linkage. According to preferred embodiments, the coupling is conducted in a solvent selected from the group consisting of, CH.sub.3CN, CH.sub.3Cl, and CH.sub.2Cl.sub.2 at a temperature between 20 C. to 60 C. Additionally or optionally, the coupling is conducted in CH.sub.2Cl.sub.2 with the presence of a powdered molecular sieve at 40 C.

Disclosed herein a sialyl donor and its use for the synthesis of gangliosides. The sialyl donor has the structure of, ##STR00001##
wherein, R.sub.1 and R.sub.2 are independently benzoyl, toluenesulfonyl, pivaloyl or acetyl optionally substituted with a halogen; and R.sub.3 is acetyl or (O)CCH.sub.2OH. In one preferred embodiment, in the sialyl donor of formula (I), R is acetyl. Also disclosed herein is a method of synthesizing a sialoside. The method comprises steps of: coupling the sialyl donor of formula (I) with a glycosyl acceptor having a primary hydroxyl group in the presence of N-iodosuccinimide (NIS) and trifluoromethanesulfonic acid (TfOH) under suitable conditions; and isolating the sialoside, which has an -glycosidic linkage. According to preferred embodiments, the coupling is conducted in a solvent selected from the group consisting of, CH.sub.3CN, CH.sub.3Cl, and CH.sub.2Cl.sub.2 at a temperature between 20 C. to 60 C. Additionally or optionally, the coupling is conducted in CH.sub.2Cl.sub.2 with the presence of a powdered molecular sieve at 40 C.

Compounds of Formula (A) are described herein and the uses thereof for the treatment of diseases, conditions and/or disorders mediated by pharmaceutical compositions and the uses thereof as asialoglycoprotein receptor (ASGPR) targeting agents. ##STR00001##