Abstract: Agents against drug-resistant tumor cells comprising a 1,4-dihydropyridine derivative represented by the following formula (I): ##STR1## wherein R.sup.1 is an aryl group which may be substituted;R.sup.2 and R.sup.3, which may be the same or different, each is a member selected from the group consisting of an alkyl group, an alkyloxycarbonyl group, an aryloxycarbonyl group, an aralkyloxycarbonyl group, an aminocarbonyl group, a hydroxycarbonyl group, a formyl group, and a cyano group, each of which may be substituted;R.sup.4 and R.sup.5 is a hydrogen atom or a member selected from the group consisting of a lower alkyl group, a hydroxymethyl group, a cyano group, an amino group, a formyl group, and a halogen atom; andR.sup.

Abstract: A new process is disclosed for preparing N-acylcarnosine which comprises reacting histidine with 3-acylaminopropionic acid reactive derivatives under basic conditions, and 3-acylaminopropionic acid reactive derivative being acid chloride, mixed acid anhydride salt with sulfuric acid, mixed acid anhydride with mono alkyl carbonate or mixed acid anhydride with phosphoric acid derivatives.

Abstract: There are disclosed novel compounds which are extracted with an organic solvent from Eupatorium sachalinense belonging to the genus Eupatorium and isolated by normal separating and refining procedures, the compounds being expressed by the general formula: ##STR1## where R is ##STR2## a pale yellowish oily substance having an optical rotation of [.alpha.].sub.D.sup.24 -121.degree. (C=O.75, ethanol), a molecular weight of 420 estimated from peak value in mass spectrum measurement (theoretical value: 420), a molecular formula of C.sub.22 H.sub.28 O.sub.8, an end absorption at 210 mm (.epsilon.:14800) in ultraviolet absorption spectrum, peaks in infrared absorption spectrum by liquid film method at the frequencies (cm.sup.-1) of 3400, 2920, 2845, 1760, 1740, 1705, 1658, 1440, 1370, 1325, 1220-1280, 1180, 1133, 1107, 1070, 1020, 970, 881, 840, 819, 788, 758, 710, 662, 630, 607 and 582, assignments of respective protons in NMR spectrum (.delta.,CDCl.sub.3) at C.sub.6 --H=5.96 (1H, dd, J=11,2), C.sub.4 --CH.sub.