The purpose of the present invention is to provide a protecting group which improves the solubility of a compound having a functional group protected with the protecting group in an organic solvent and which is easily separated and purified after a reaction with avoiding solidification or insolubilization. Provided is a benzyl compound represented by Formula (1) where X.sup.1 represents CH.sub.2OR.sup.14 (where R.sup.14 represents a hydrogen atom, a halogenocarbonyl group, or an active ester-type protecting group), CH.sub.2NHR.sup.15 (where R.sup.15 represents a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, or an aralkyl group), a halogenomethyl group, a methyl azide group, a formyl group, or an oxime; and at least one of R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 is a group represented by Formula (2), and the remainders each represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms, where R.sup.6 represents a linear or branched alkylene group having 1 to 16 carbon atoms; X.sup.2 represents O or CONR.sup.16 (where R.sup.16 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms); and A represents a group represented by Formula (3), (4), (5), (6), (7), (8), (9), (10), (11), (12), or (13).

The invention relates to ?-amaninamide (1; x=0, 1 or 2), ?-amaninamidic acid (2; x=0, 1 or 2), and ?-amaninamidic hydroxamic acid (3; x=0, 1 or 2), novel derivatives of ?-amanitin (4), and methods and novel building blocks for the synthesis thereof.

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The invention relates to novel methods for synthesizing a synthon for ,-dihydroxyisoleucine 1 (CAS No. 55399-94-5] as building block for the synthesis of amatoxins, and for novel methods for synthesizing amatoxins using such building block. ##STR00001##

Provided are a method for producing a peptide compound including a step of using a compound represented by Formula (1); a protective group-forming reagent including the compound; and the compound. At least one of R.sup.1 to R.sup.8 or Y.sup.2 has R.sup.A, R.sup.A represents an aliphatic hydrocarbon group or an organic group having an aliphatic hydrocarbon group, and the number of carbon atoms in at least one aliphatic hydrocarbon group is 12 or more. However, R.sup.A does not have a silyl group and a hydrocarbon group having a silyloxy structure. ##STR00001##

The present invention relates to Muramyl dipeptide compounds having adjuvant activity. The present invention also discloses the process for the preparation of Muramyl dipeptide compound and their intermediates. The immuno-modulating properties of the Muramyl dipeptide compound and their use as NOD2 agonistic adjuvants in vaccine formulations is also disclosed.