Method for treating cocainism

A method for activating cholinesterase, comprising administering a compound having a prolyl endopeptidase inhibitory activity to treat cocainism, is disclosed.

FIELD OF THE INVENTION 
The present invention relates to a method for activating cholinesterase. 
More particularly, the present invention relates to a method for 
activating cholinesterase using a compound having prolyl endopeptidase 
inhibitory activity and a method for treating cocainism by the activation 
of cholinesterase using said compound. 
BACKGROUND OF THE INVENTION 
Cocaine is an alkaloid contained in coca (Erythroxylon coca) leaves a 
originally came from South America. It causes intense excitation, produces 
a dependency, and created a serious social problem of cocainism. 
Cocaine directly acts on the peripheral sensory nerve fiber to reversively 
paralyze the same, and shuts down production and conduction of afferent 
impulses. 
The pharmacological actions of cocaine include local anesthesia. Cocaine is 
advantageous in that it readily penetrates mucous membrane and infiltrates 
into tissues, and that it causes vasoconstriction to retard its systemic 
absorption, thereby prolonging anesthesia. 
The systemic effect produced by absorption is found in the central nervous 
system and cardiovascular system. Noticeable excitation proceeds from the 
upper site to the lower site in the CNS. Thus, at a lower dose, it first 
acts on the cerebral cortex to manifest mental uplift, the sense of 
increased intelligence, disappearance of fatigue, euphoria and 
hyperkinesis. Such condition characterized by feeling of being refreshed 
and possession of increased mental and physical capabilities is called 
cocaine drunkenness. 
On the other hand, its use in higher doses causes hallucination, 
derangement, berserk, tremor, clonic spasm, and respiratory excitation, 
elevation of blood pressure and body temperature, emesis and the like, all 
of which are caused by stimulation of medulla oblongata, and which in turn 
progress into suppression (e.g., coma), suppression of respiratory and 
cardiac functions and suppression of reflex mechanism of spinal cord. When 
continuously used, psychopathic symptoms such as anxiety, agrypnia, 
hallucination, delusion, derangement and the like, and physical symptoms 
of mydriasis, tachycardia, fervescence, convulsion and the like are 
observed. The mydriasis is also caused by peripheral(sympathetic) action 
of cocaine. Associated with such psychopathic symptoms, cocaine is 
classified as a narcotic. 
As a narcotic, cocaine is characterized by the fact that it seldom shows 
physical dependency but shows extremely strong psychological dependency. 
In a low or medium dose, its action on the cardiac function is secondary, 
resulting from its primary action on central and peripheral nerves. When a 
higher dose is intravenously administered, however, it may directly act on 
the myocardium to cause cardiac dysfunction. There have been also found 
central and peripheral actions on blood vessels. It inhibits catecholamine 
uptake at the adrenergic nerve ending and enhances action of 
norepinephrine on the vascular wall. 
A cholinesterase is an enzyme which hydrolyzes choline ester into choline 
and organic acid. There exist two types of the enzyme in the living body; 
acetylcholinesterase (true cholinesterase; EC 3.1.1.7) and cholinesterase 
(serum cholinesterase, pseudocholinesterase; EC 3.1.1.8). The former 
resides in the nerve tissues, muscles, erythrocytes and the like, and 
specifically decomposes acetylcholine. The latter is synthesized in the 
liver and secreted into serum. While its biological role has not been 
fully elucidated, it decomposes, besides acetylcholine, various choline 
esters and non-choline esters. 
The metabolism of cocaine is complicated, since it depends on various 
enzyme activities, doses and administration routes. The major metabolites 
are three compounds; norcocaine, benzoylecgonine and ecgonine methylester. 
Given a report on the use of an organophosphate insecticide (cholinesterase 
inhibitor) for prolongation of cocaine excitement and a report which 
indicates that the metabolism of cocaine is shifted largely toward 
benzoylecgonine, but also somewhat toward norcocaine at low cholinesterase 
activity, Hoffman et al. documented a report which concludes, "when plasma 
cholinesterase activity is low, 1) metabolism of cocain is slowed and its 
toxicity is prolonged, 2) metabolism of cocain is shunted away from the 
nontoxic ecgonine methylester and toward the active metabolite norcocaine 
or potentially active metabolite benzoylecgonine." They conclude that the 
both mechanisms in combination enhance cocaine toxicity and that, by 
reference to recent findings, serum cholinesterase activity is considered 
to be an important determinant of cocaine toxicity (Journal of Toxicology, 
Clinical Toxicology, 34 (3), 259-266 (1996)). Therefore, once the serum 
cholinesterase activity can be improved, the above-mentioned problems will 
be solved, and the treatment of cocainism will be facilitated. 
The present inventors have surprisingly found that a compound having a 
prolyl endopeptidase inhibitory activity can specifically activate the 
serum cholinesterase activity. Hence, administration of a compound having 
a prolyl endopeptidase inhibitory activity to patients will lead to the 
cure of cocainism. 
SUMMARY OF THE INVENTION 
The inventive method for activating cholinesterase and a treatment method 
of cocainism are characterized by the use of a compound having a prolyl 
endopeptidase inhibitory activity, and specifically include the following 
(1) to (8). 
(1) A method for activating cholinesterase, comprising using a compound 
having a prolyl endopeptidase inhibitory activity. 
(2) The method for activating cholinesterase of (1) above, wherein the 
compound having a prolyl endopeptidase inhibitory activity is represented 
by the formula [I] 
##STR1## 
wherein: R.sup.1 is a hydrogen atom, a lower alky, a phenoxy, an 
adamantyl, a hetero ring optionally substituted by a lower alkyl, a 
halogen atom, a hydroxy, a lower alkoxy, an amino, a nitro, a 
trifluoromethyl or an oxo, a group of the formula 
##STR2## 
wherein R.sup.3 is a hydrogen atom, a halogen atom, a lower alkyl, a 
hydroxy, a lower alkoxy, an amino or a trifluoromethyl, or 
a group of the formula 
##STR3## 
wherein R.sup.4 is a hydrogen atom, a halogen atom, a lower alkyl, a lower 
alkoxy, an amino or a nitro, R.sup.5 is a hydrogen atom or a lower alkyl, 
A is a methylene, an ethylene or a propylene, and -------- shows a single 
bond or a double bond; 
R.sup.2 is a hydrogen atom, a carboxyl, a lower alkoxycarbonyl, a formyl, a 
hydroxymethyl, 
##STR4## 
wherein R.sup.6 is a hydrogen atom, a lower alkyl, an acyl, a group of the 
formula 
##STR5## 
wherein ring D is a benzene ring or a hetero ring, R.sup.7 and R.sup.8 are 
the same or different and each is a hydrogen atom, a halogen atom, a lower 
alkyl optionally substituted by fluorine atom, a hydroxy, a lower alkoxy, 
an amino or a nitro, R.sup.7 and R.sup.8 may in combination form a 
saturated or unsaturated 5- or 6-membered ring, and p is an integer of 0 
or 1-3, 
B is an oxygen atom, a sulfur atom, a sulfinyl, a sulfonyl, NH or a single 
bond, and n is an integer of 1-6, or 
a group of the formula 
##STR6## 
wherein R.sup.9 is a hydrogen atom, a halogen atom or an acyloxy, and 
R.sup.10 is a diphenylmethyl, a trityl, a lower alkyl optionally 
substituted by a halogen atom or a group of the formula 
##STR7## 
wherein R.sup.11 and R.sup.12 are the same or different and each is a 
hydrogen atom, a halogen atom or a lower alkoxy, or 
##STR8## 
wherein R.sup.13, R.sup.14 and R.sup.15 are the same or different and each 
is a lower alkyl or a phenyl; 
U is an oxygen atom, a sulfur atom, a carbonyl, --CHR.sup.16 -- wherein 
R.sup.16 is a hydrogen atom or a lower alkoxycarbonyl, --NR.sup.17 -- 
wherein R.sup.17 is a hydrogen atom, an alkyl having 1 to 8 carbon atoms, 
a cycloalkyl having 3 to 7 carbon atoms, a phenyl, a benzyl, an acyl or a 
lower alkoxycarbonyl, or a single bond; 
V is an oxygen atom, --CHR.sup.18 -- wherein R.sup.18 is a hydrogen atom or 
a hetero ring, --NR.sup.19 -- wherein R.sup.19 is a hydrogen atom or a 
lower alkoxycarbonyl lower alkyl, or a single bond; 
##STR9## 
wherein R.sup.20 is a hydrogen atom or a lower alkyl, R.sup.21 is a 
hydrogen atom, a lower alkyl or --(CH.sub.2).sub.r --R.sup.22 wherein 
R.sup.22 is a hydrogen atom, a branched alkyl having 3 to 5 carbon atoms, 
a lower alkylthio, a phenyl, a phenyl substituted by hydroxy, 
benzyloxyphenyl, hydroxy, lower alkoxy, benzyloxy, amino, 
benzyloxycarbonylamino, carboxyl, benzyloxycarbonyl, indolyl, imidazolyl, 
or a bond of carbon atom and nitrogen atom together with R.sup.20 and r is 
an integer of 0 or 1-8, and Y is a methylene or a sulfur atom, 
an alkylene having 1 to 8 carbon atoms, an alkenylene having 2 to 8 carbon 
atoms or a saturated hydrocarbon ring having 3 to 7 carbon atoms; 
X is a methylene or a sulfur atom; and 
m is an integer of 0 or 1-8. 
(3) The method for activating cholinesterase of (2) above, wherein the 
compound having the prolyl endopeptidase inhibitory activity is a compound 
of the formula [I] 
wherein 
R.sup.1 is a methyl, a hetero ring or 
##STR10## 
wherein R.sup.3 ' is a hydrogen atom, a halogen atom, a lower alkyl, a 
hydroxy, a lower alkoxy or an amino; 
R.sup.2 is 
##STR11## 
wherein R.sup.6 ' is a hydrogen atom or an acyl and n' is an integer of 
1-4; 
U is an oxygen atom, a sulfur atom, --CHR.sup.16 -- wherein R.sup.16 is as 
defined at above, or --NR.sup.17 '-- wherein R.sup.17 ' is a hydrogen atom 
or a lower alkoxycarbonyl; 
V is an oxygen atom, --CHR.sup.18 -- wherein R.sup.18 is as defined above, 
--NR.sup.9 -- wherein R.sup.19 is as defined above; and 
W is 
##STR12## 
wherein Y is as defined above; and m is an integer of 0 or 1-6. 
(4) The method for activating choline sterase of (1) above, wherein the 
compound having the prolyl endopeptidase inhibitory activity is 
represented by the formula [II] 
##STR13## 
wherein R.sup.23 is a lower alkyl and E is a protecting group of 
N-terminal in the amino acid chemistry or an acyl of an amino acid having 
a protecting group at the N-terminal. 
(5) The method for activating cholinesterase of (3) above, wherein the 
compound having the prolyl endopeptidase inhibitory activity is 
(2S)-1-benzylaminocarbonyl-[(2S)-2-glycolylpyrrolidinyl]-2-pyrrolidinecarb 
oxamide. 
(6) A method for treating cocainism, comprising administering a 
pharmaceutically effective amount of a compound having a prolyl 
endopeptidase inhibitory activity. 
(7) The method for treating cocainism according to (6) above, wherein the 
compound having the prolyl endopeptidase inhibitory activity is a compound 
of the formula [I]. 
(8) The method for treating cocainism according to (7) above, wherein the 
compound having the prolyl endopeptidase inhibitory activity is a compound 
of the formula [I] wherein R.sup.1 is a methyl, a hetero ring or 
##STR14## 
wherein R.sup.3 ' is a hydrogen atom, a halogen atom, a lower alkyl, a 
hydroxy, a lower alkoxy or an amino; R.sup.2 is 
##STR15## 
wherein R.sup.6 ' is a hydrogen atom or an acyl and n' is an integer of 
1-4; U is an oxygen atom, a sulfur atom, --CHR.sup.16 -- wherein R.sup.16 
is as defined above, or --NR.sup.17 '-- wherein R.sup.17 ' is a hydrogen 
atom or a lower alkoxycarbonyl; V is an oxygen atom, --CHR.sup.18 -- 
wherein R.sup.18 is as defined above, or --NR.sup.19 -- wherein R.sup.19 
is as defined above; W is 
##STR16## 
wherein Y is as defined above; and m is an integer of 0 or 1-6. (9) The 
method for treating cocainism according to (6) above, wherein the compound 
having the prolyl endopeptidase inhibitory activity is a compound of the 
formula [II]. 
(10) The method for treating cocainism according to (8) above, wherein the 
compound having the prolyl endopeptidase inhibitory activity is 
(2S)-1-benzylaminocarbonyl-[(2S)-2-glycolylpyrrolidinyl]-2-pyrrolidine-carb 
oxamide.

DETAILED DESCRIPTION OF THE INVENTION 
The compound having a prolyl endopeptidase inhibitory activity in the 
present invention includes any compound having inhibitory activity on an 
enzyme called prolyl endopeptidase. A first example of such compound is a 
compound having the above-mentioned formula [I], which specifically 
exemplified by the following compounds. Note that m and n designating an 
integer in the following formulas [I-a] to [I-j] are used solely in the 
context of the corresponding formula. 
The compound disclosed in U.S. Pat. No. 5,536,737, which is represented by 
the formula [I-a]: 
##STR17## 
wherein R.sup.a is a hydrogen atom or an acyl; U.sup.a is --O--, 
--CHR.sup.1a -- wherein R.sup.1a is a hydrogen atom or a hetero ring, or 
--NR.sup.2a -- wherein R.sup.2a is a hydrogen atom or a lower 
alkoxycarbonyl lower alkyl; V.sup.a is --O--, --S--, --CHR.sup.3a -- 
wherein R.sup.3a is a hydrogen atom or a lower alkoxycarbonyl or 
--NR.sup.4a -- wherein R.sup.4a is a hydrogen atom, a lower alkyl or an 
acyl; W.sup. a is a methyl, a hetero ring or 
##STR18## 
wherein R.sup.5a is a hydrogen atom, a halogen atom, a lower alkyl, an 
amino, a hydroxy or a lower alkoxy; 
X.sup.a and Y.sup.a are the same or different and each is --CH.sub.2 -- or 
--S--; 
m is an integer of 0-6; and n is an integer of 1-4. 
Examples of the compound of the formula [I-a] include 
(S)-2-[[(S)-2-(acetoxyacetyl)-1-pyrrolidinyl]carbonyl]-N-(phenylmethyl)-1- 
pyrrolidinecarboxamide, 
(S)-2-[[(S)-2-(hydroxyacetyl)-1-pyrrolidinyl]carbonyl]-N-(phenylmethyl)-1- 
pyrrolidinecarboxamide, 
(S)-2-[[(S)-2-(benzoyloxyacetyl)-1-pyrrolidinyl]carbonyl]-N-(phenylmethyl) 
-1-pyrrolidinecarboxamide and the like. 
The compound disclosed in U.S. Pat. No. 5,506,256, which is represented by 
the formula [I-b]: 
##STR19## 
wherein: A.sup.b is 
##STR20## 
or a single bond; B.sup.b is 
##STR21## 
W.sup.b is 
##STR22## 
or CH.sub.3 -- where R.sup.1b is a hydrogen atom, a halogen atom or a 
lower alkoxy; 
X.sup.b is --S--, --SO--, --SO2--, --O-- or --NH--; 
R.sup.b is 
##STR23## 
or a lower alkyl having 1 to 5 carbon atoms where 1 is an integer of 0 to 
3, Y.sup.b and Z.sup.b are the same or different and each is a hydrogen 
atom, a halogen atom, a lower alkyl having 1 to 5 carbon atoms which may 
be substituted by fluorine atoms, a nitro, a hydroxy or a lower alkoxy, 
and Y.sup.b and Z.sup.b may combinedly form a saturated or unsaturated 5- 
or 6-membered ring selected from the group consisting of furan ring, 
oxolane ring, 1,3-dioxolane ring, thiophene ring, pyrrole ring, 
pyrrolidine ring, oxane ring, pyridine ring and benzene ring; and n is an 
integer of 1 to 6. 
Examples of the compound of the formula [I-b] include 
(2S)-1-(N-benzylaminocarbonyl-L-prolyl)-2-(phenoxyacetyl)pyrrolidine, 
(2S)-1-(N-benzyloxycarbonyl-L-prolyl)-2-[(phenylthio)acetyl]pyrrolidine, 
(2S)-1-(N-benzyloxycarbonyl-L-prolyl)-2-[1-hydroxy-2-(phenylsulfonyl)ethyl 
]pyrrolidine and the like. 
The compound disclosed in U.S. Pat. No. 5,506,256, which is represented by 
the formula [I-c]: 
##STR24## 
wherein: A.sup.c is --O--, --CHR.sup.1c -- or --NR.sup.2c -- (wherein 
R.sup.1c is a hydrogen atom or a hetero ring, and R.sup.2c is a lower 
alkoxycarbonyl(lower)alkyl; 
B.sup.c is 
##STR25## 
or --NR.sup.3c --CHR.sup.4c -- (wherein R.sup.3c and R.sup.4c are the 
same or different, and each is a hydrogen atom or a lower alkyl); 
W.sup.c is a phenyl which may be substituted by at least one substituent 
selected from the group consisting of a halogen atom, a lower alkyl and a 
lower alkoxy, an adamantyl, a lower alkyl and a hetero ring; 
U.sup.c is --O--, --S--, --NH-- or --CHR.sup.5c -- (wherein R.sup.5c is a 
hydrogen atom or a lower alkoxycarbonyl); 
X.sup.c is --S--, --SO--, --SO.sub.2 --, --O-- or --NH--; and 
R.sup.c is 
##STR26## 
(wherein D.sup.c is a benzene ring or a hetero ring, Y.sup.c and Z.sup.c 
are the same or different and each is a hydrogen atom, a halogen atom, a 
lower alkyl which may be substituted by at least one fluorine atom, amino, 
nitro, hydroxy or a lower alkoxy) 
with the proviso that when U.sup.c is --CH.sub.2 --, at least W.sup.c is 
adamantyl or a hetero ring, or A.sup.c is --CHR.sup.1c -- or --NR.sup.2c 
-- (wherein R.sup.1c is a hetero ring and R.sup.2c is a lower 
alkoxycarbonyl(lower)alkyl), B.sup.c is thiazolidine, or R.sup.c is a 
hetero ring. 
Examples of the compound of the formula [I-c] include 
(2S)-2-(4-methoxyphenoxyacetyl)-1-[N-[(phenylthio)acetyl]-L-prolyl]pyrroli 
dine, 
(2S)-1-[N-(benzylaminocarbonyl)-L-thioprolyl]-2-(phenoxyacetyl)pyrrolidine 
, (2S)-1-[N-[N-benzyl-N-(ethoxycarbonylmethyl)aminocarbonyl]-L-prolyl]-2-(p 
henoxyacetyl)pyrrolidine and the like. 
The compound disclosed in Japanese Patent Unexamined Publication No. 
3132/1996, which is represented by the formula [I-d]: 
##STR27## 
wherein R.sup.1d is an optionally substituted aryl or an optionally 
substituted heteroaryl; R.sup.2d is a hydrogen atom, a halogen atom or an 
acyloxy; R.sup.3d is a carboxyl-protecting group; A.sup.d is an oxygen 
atom, NH or CH.sub.2 ; and n is an integer of 1-3. 
Examples of the compound of the formula [I-d] include 
(S)-2-[[(S)-2-[(2R,S)-2-acetoxy-2-(ethoxycarbonyl)acetyl]-1-pyrrolidinyl]c 
arbonyl]-N-(phenylmethyl)-1-pyrrolidinecarboxamide, 
(S)-2-[[(S)-2[(2R,S)-2acetoxy-2-(benzyloxycarbonyl)acetyl]-1-pyrrolidinyl] 
carbonyl]-N-(phenylmethyl)-1-pyrrolidinecarboxamide and the like. 
The compound disclosed in U.S. Pat. No. 4,873,342, which is represented by 
the formula [I-e]: 
##STR28## 
wherein m is an integer of 1-8; n is an integer of 1-6; R.sup.1e is a 
hydrogen atom; R.sup.2e is a hydrogen atom, a branched alkyl having 3 to 5 
carbon atoms, a phenyl, a hydroxyphenyl, an indolyl, an imidazolyl or a 
methylthio; or R.sup.1e and R.sup.2e combinedly show a carbon-nitrogen 
bond; and R.sup.3e is a lower alkyl ester, a hydroxymethyl or a formyl. 
Examples of the compound of the formula [I-e] include 
N-[N-(4-phenylbutanoyl)norleucyl]-prolinal, 
N-[N-(4-phenylbutanoyl)phenylalanyl]-prolinal, 
N-[N-(4-phenylbutanoyl)methionyl]-prolinal and the like. 
The compound disclosed in U.S. Pat. Nos. 4,826,870 and 5,198,458, which is 
represented by the formula [I-f]: 
##STR29## 
wherein m is an integer of 0 or 1-7; n is an integer of 0 or 1-8; R.sup.f 
is a phenyl, a substituted phenyl, a phenoxy or a substituted phenoxy; 
R.sup.1f is a hydrogen atom; R.sup.2f is a hydrogen atom, a branched alkyl 
having 3 to 5 carbon atoms, a phenyl, a hydroxyphenyl, a benzyloxyphenyl, 
an alkylthio containing an alkyl having 1 to 3 carbon atoms, an amino, a 
benzyloxycarbonylamino, a carboxyl, a carboxylic acid benzyl ester group, 
a hydroxy, a benzyloxy, an indolyl or an imidazolyl; or R.sup.1f and 
R.sup.2f combinedly show a carbon-nitrogen bond; provided that when m is 
0, R.sup.f is arylalkyloxy having 7 to 9 carbon atoms and R.sup.1f and 
R.sup.2f combinedly show a carbon-nitrogen bond. 
The compound of the formula [I-f] includes, for example, 
N-(.gamma.-phenyl)butanoyl-L-valyl-pyrolidinimide, 
N-(.gamma.-phenyl)butanoyl-L-leucyl-pyrrolidinimide and the like. 
The compound disclosed in U.S. Pat. No. 4,857,524, which is represented by 
the formula [I-g]: 
##STR30## 
wherein 
##STR31## 
is a 5- or 6-membered saturated hetero ring which may include hetero atom 
other than N; and R.sup.g is a hydrogen atom or an alkoxycarbonyl. 
Examples of the compound of the formula [I-g] include 
3-[(R)-(--)-3-carbobenzoxythiazolidine-4-carbonyl]thiazolidine, 
3-[(R)-(--)-3-carbobenzoxythiazolidine-4-carbonyl]pyrrolidone and the 
like. 
The compound disclosed in U.S. Pat. Nos. 4,956,380, 5,100,904, 5,254,550 
and 5,340,832, which is represented by the formula [I-h]: 
##STR32## 
wherein A.sup.h is an alkylene having 1 to 8 carbon atoms, an alkenylene 
having 2 to 8 carbon atoms or a saturated hydrocarbon ring having 3 to 7 
carbon atoms; R.sup.h is a hydrogen atom, a phenyl, a benzyl, an alkyl 
having 1 to 8 carbon atoms or a cycloalkyl having 3 to 7 carbon atoms; 
B.sup.h is a single bond or an alkylene having 1 to 8 carbon atoms which 
may be substituted by phenyl or benzyl; and D.sup.h is a carbon ring or 
hetero ring which is unsubstituted or substituted by 1 to 3 member(s) 
selected from halogen atom, alkyl, alkoxy having 1 to 4 carbon atoms, 
nitro and trifluoromethyl. 
Examples of the compound of the formula [I-h] include 
N-[3-[N-(2-phenylethyl)carbamoyl]propanoyl]-L-prolinal, 
N-[3-(N-benzylcarbamoyl)-propanoyl]-L-prolinal, 
N-[3-[N-(4-chlorophenylmethyl)-N-phenylcarbamoyl]propanoyl-L-prolinal and 
the like. 
The compound disclosed in U.S. Pat. No. 5,028,604, which is represented by 
the formula [I-i]: 
##STR33## 
wherein A.sup.i is a methylene, an ethylene or a propylene; B.sup.i is a 
methylene or an ethylene; m is an integer of 0-5; X.sup.i and Y.sup.i are 
different and each is a methylene or a sulfur atom; R.sup.1i is a hydrogen 
atom, a carboxyl, a lower alkyl ester, a hydroxymethyl or a formyl; 
R.sup.2i is a hydrogen atom, a halogen atom, a lower alky, a lower alkoxy, 
a nitro or an amino; R.sup.3i is a hydrogen atom or a lower alkyl; and 
------ is a single bond or a double bond. 
Examples of the compound of the formula [I-i] include methyl 
1-(2-indanylacetyl)-L-prolinate, 
1-[3-(2-indanylacetyl)-L-thioprolyl]pyrrolidine and the like. 
The compound disclosed in Japanese Patent Unexamined Publication No. 
9367/1992, which is represented by the formula [I-j]: 
##STR34## 
wherein A.sup.j is a thienyl, a benzofuranyl, a benzothiophenyl, an 
indolyl, a 2,3-dihydrobenzofuranyl, a chromanyl, a 
4,5,6,7-tetrahydrobenzothiophenyl, a 4,5,6,7-tetrahydrobenzofuranyl or a 
1-oxoindanyl; m is an integer of 0-5; and X.sup.j and Y.sup.j are the same 
or different and each is a methylene or a sulfur atom. 
Examples of the compound of the formula [I-j] include 
1-(thiophen-2-ylcarbonyl)-L-thioproline and the like. 
A second example of the compound having a prolyl endopeptidase inhibitory 
activity is a compound of the above-mentioned formula [II] which is 
exemplified by the compound disclosed in U.S. Pat. No. 5,158,970 having 
the formula [II-k]: 
##STR35## 
wherein R.sup.k is a lower alkyl; and X.sup.k is a protecting group at the 
N-terminal in amino acid chemistry or acyl of an amino acid having a 
protecting group at the N-terminal. 
Examples of the compound of the formula [II-k] include 
p-methoxybenzoyl-L-prolynal dimethylacetal, 
N-benzyloxycarbonyl-L-prolyl-L-prolinal diethylacetal and the like. 
As used herein, lower alkyl is a linear or branched alkyl having 1 to 6 
carbon atoms, which is exemplified by methyl, ethyl, propyl, isopropyl, 
butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl, 
hexyl, isohexyl, neohexyl and the like, with preference given to a linear 
or branched alkyl having 1 to 4 carbon atoms which is specifically methyl, 
ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl and the 
like. 
The lower alkyl of "lower alkyl having 1 to 5 carbon atoms" and "lower 
alkyl having 1 to 5 carbon atoms which may be substituted by fluorine 
atom" is exemplified by the above-mentioned lower alkyl having 1 to 5 
carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, 
sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl and the like. Examples 
of the lower alkyl having 1 to 5 carbon atoms which is substituted by 
fluorine atom include trifluoromethyl, difluoromethyl, fluoromethyl and 
the like. 
The lower alkyl of "lower alkyl optionally substituted by at least one 
fluorine atom" and the lower alkyl of "lower alkyl optionally substituted 
by halogen atom" are the same as those defined above. The lower alkyl 
substituted by at least one fluorine atom may be, for example, 
trifluoromethyl, difluoromethyl, fluoromethyl and the like; and lower 
alkyl substituted by halogen atom may be, for example, 
2,2,2-trichloroethyl, 2-chloroethyl, 3-chloropropyl and the like. 
The branched alkyl having 3 to 5 carbon atoms means, for example, 
isopropyl, isobutyl, sec-butyl, tert-butyl, isopentyl, neopentyl, 
tert-pentyl and the like. 
The alkyl having 1 to 8 carbon atoms is a linear or branched alkyl having 1 
to 8 carbon atoms, which is specifically methyl, ethyl, propyl, butyl, 
pentyl, hexyl, heptyl, octyl, isomers thereof and the like. 
The cycloalkyl having 3 to 7 carbon atoms is specifically cyclopropyl, 
cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl and the like. 
The alkylene having 1 to 8 carbon atoms is a linear or branched alkylene 
having 1 to 8 carbon atoms, which is specifically methylene, ethylene, 
trimethylene, tetramethylene, pentamethylene, hexamethylene, 
heptamethylene, octamethylene and isomers thereof, with preference given 
to those having 1 to 4 carbon atoms. The alkylene of "alkylene having 1 to 
8 carbon atoms which is optionally substituted by phenyl or benzyl" is as 
defined above. 
The alkenylene having 2 to 8 carbon atoms is the above-mentioned alkylene 
but not methylene, and has an optional number of double bond. Preferred 
are those having one double bond and 2 to 4 carbon atoms. 
The saturated hydrocarbon ring having 3 to 7 carbon atoms is specifically 
cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, 
cyclooctane and the like. 
The halogen atom is fluorine atom, chlorine atom, bromine atom, iodine atom 
and the like. 
The lower alkoxy is a linear or branched alkoxy having 1 to 6 carbon atoms, 
which is specifically methoxy, ethoxy, propoxy, isopropoxy, butoxy, 
isobutoxy, sec-butoxy, tert-butoxy, pentyloxy, isopentyloxy, neopentyloxy, 
tert-pentyloxy, hexyloxy, isohexyloxy, neohexyloxy and the like, with 
preference given to a linear or branched alkoxy having 1 to 4 carbon 
atoms. Specific examples thereof include methoxy, ethoxy, propoxy, 
isopropoxy, butoxy, isobutoxy, sec-butoxy, tert-butoxy and the like. 
The lower alkylthio is a linear or branched alkylthio having 1 to 6 carbon 
atoms, which is specifically methylthio, ethylthio, propylthio, 
isopropylthio, butylthio, isobutylthio, sec-butylthio, tert-butylthio, 
pentylthio, isopentylthio, neopentylthio, tert-pentylthio, hexylthio, 
isohexylthio, neohexylthio and the like, with preference given to a linear 
or branched alkylthio having 1 to 4 carbon atoms. Specific examples 
thereof include methylthio, ethylthio, propylthio, isopropylthio, 
butylthio, isobutylthio, sec-butylthio, tert-butylthio and the like. The 
alkylthio containing alkyl having 1 to 3 carbon atoms is exemplified by 
methylthio, ethylthio, propylthio, isopropylthio and the like. 
The alkoxycarbonyl is specifically methoxycarbonyl, ethoxycarbonyl, 
propoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl, isobutoxycarbonyl, 
sec-butoxycarbonyl, tert-butoxycarbonyl, pentyloxycarbonyl, 
isopentyloxycarbonyl, neopentyloxycarbonyl, tert-pentyloxycarbonyl, 
hexyloxycarbonyl, isohexyloxycarbonyl, neohexyloxycarbonyl and the like, 
with preference given to alkoxycarbonyl having 2 to 5 carbon atoms. 
Specific examples thereof include methoxycarbonyl, ethoxycarbonyl, 
propoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl, isobutoxycarbonyl, 
sec-butoxycarbonyl, tert-butoxycarbonyl and the like. The lower 
alkoxycarbonyl means those having 2 to 7 carbon atoms. 
The lower alkoxycarbonyl lower alkyl is the above-mentioned alkyl having 1 
to 5 carbon atoms which is substituted by lower alkoxycarbonyl. Examples 
thereof include methoxycarbonylmethyl, 2-(methoxycarbonyl)ethyl, 
3-(methoxycarbonyl)propyl, ethoxycarbonylmethyl, 2-(ethoxycarbonyl)ethyl, 
3-(ethoxycarbonyl)propyl, propoxycarbonylmethyl, 2-(propoxycarbonyl)ethyl, 
3-(propoxycarbonyl)propyl and the like. 
The acyl is a linear or branched alkanoyl having 1 to 6 carbon atoms; 
(hetero)arylcarbonyl having 3 to 11 carbon atoms, which may have hetero 
atom selected from oxygen, nitrogen and sulfur; or (hetero)arylalkanoyl 
having 4 to 14 carbon atoms, which may have hetero atom selected from 
oxygen, nitrogen and sulfur. Examples of alkanoyl include formyl, acetyl, 
propionyl, isopropionyl, butyryl, isobutyryl, pivaloyl, valeryl, 
isovaleryl, caproyl, isocaproyl and the like. Examples of 
(hetero)arylcarbonyl include benzoyl, naphthoyl, nicotinoyl, 
isonicotinoyl, thenoyl, furoyl, pyrrolylcarbonyl, pyrazolylcarbonyl, 
imidazolylcarbonyl, pyrazinylcarbonyl, pyrimidinylcarbonyl, 
triazolylcarbonyl, thiazolylcarbonyl, benzofuranylcarbonyl, 
indolylcarbonyl, benzotriazolylcarbonyl and the like. Examples of 
(hetero)arylalkanoyl include phenylacetyl, phenylpropionyl, 
naphthylacetyl, naphthylpropionyl, pyridylacetyl, thienylacetyl, 
thienylbutyryl, imidazolylacetyl, thiazolylacetyl, indolylacetyl, 
indolylpropionyl and the like. Preferred are alkanoyl having 2 to 5 carbon 
atoms, such as acetyl, propionyl, isopropionyl, butyryl, isobutyryl, 
pivaloyl, valeryl and isovaleryl; (hetero)arylcarbonyl having 4 to 7 
carbon atoms, which may have a hetero atom selected from oxygen, nitrogen 
and sulfur, such as benzoyl, naphthoyl, nicotinoyl, isonicotinoyl, 
thenoyl, furoyl, pyrrolylcarbonyl, pyrazolylcarbonyl, imidazolylcarbonyl, 
pyrazinylcarbonyl, pyrimidinylcarbonyl and thiazolylcarbonyl; and 
(hetero)arylalkanoyl having 5 to 9 carbon atoms, which may have a hetero 
atom selected from oxygen, nitrogen and sulfur, such as phenylacetyl, 
phenylpropionyl, pyridylacetyl, thienylacetyl, thienylbutyryl, 
imidazolylacetyl and thiazolylacetyl, with particular preference given to 
alkanoyl having 2 to 5 carbon atoms (e.g., acetyl, propionyl, 
isopropionyl, butyryl, isobutyryl and pivaloyl); arylcarbonyl having 4 to 
7 carbon atoms (e.g., benzoyl and the like); and arylalkanoyl having 5 to 
9 carbon atoms (e.g., phenylacetyl and phenylpropionyl). The 
above-mentioned (hetero)arylcarbonyl and (hetero)arylalkanoyl may have 1 
to 3 substituent(s) on the (hetero)aryl, and the substituent is 
exemplified by halogen atom, lower alkyl, amino, hydroxy, lower alkoxy, 
carboxy, lower alkoxycarbonyl, acyl and the like. 
The acyloxy is an acyloxy having 1 to 6 carbon atoms, which is optionally 
substituted by halogen atom. Examples thereof include formyloxy, 
acetyloxy, propionyloxy, butyryloxy, valeryloxy, pivaloyloxy, 
chloroacetyloxy, trichloroacetyloxy, trifluoroacetyloxy, benzoyloxy and 
the like, with preference given to acetyloxy, pivaloyloxy and benzoyloxy, 
and particular preference given to acetyloxy. 
The hetero ring in this specification means a saturated or unsaturated 
optionally condensed 4- to 7-membered ring having 1 to 3 hetero atom(s) 
selected from oxygen, nitrogen and sulfur, which is exemplified by 
azetidine, pyrrole, pyrroline, pyrrolidine, furan, dihydrofuran, 
tetrahydrofuran, tetrahydrofuran(oxolane), 1,3-dioxolane, 
tetrahydropyran(oxane), thiophene, dihydrothiophene, tetrahydrothiophene, 
imidazole, imidazoline, imidazolidine, pyrazole, pyrazoline, pyrazolidine, 
oxazole, oxazolidine, isoxazole, isoxazolidine, thiazole, thiazolidine, 
isothiazole, isothiazolidine, furazan, pyridine, pyrimidine, pyrazine, 
piperidine, piperazine, morpholine, homopiperidine, benzofuran, 
2,3-dihydrobenzofuran, 4,5,6,7-tetrahydrobenzofuran, benzothiophene, 
2,3-dihydrobenzothiophene, 4,5,6,7-tetrahydrobenzothiophene, indole, 
indoline, chromene, chroman, quinoline and isoquinoline, with preference 
given to pyridine, piperidine and morpholine. 
The saturated or unsaturated 5- or 6-membered ring in this specification 
means, for example, cycloheptane, cycloheptene, cycloheptdiene, 
cyclohexane, cyclohexene, cyclohexdiene, benzene, pyrrole, pyrroline, 
pyrrolidine, furan, dihydrofuran, tetrahydrofuran, thiophene, 
dihydrothiophene, tetrahydrothiophene, imidazole, imidazoline, 
imidazolidine, pyrazole, pyrazolidine, oxazole, oxazolidine, isoxazole, 
isoxazolidine, thiazole, thiazolidine, isothiazole, isothiazolidine, 
furazan, pyridine, pyrimidine, pyrazine, dihydropyridine, piperidine, 
piperazine, morpholine and the like. 
The hetero atom in the hetero ring of "5- or 6-membered saturated 
heterocyclic ring which may include hetero atom other than N" is 
exemplified by O, S and the like. The saturated heterocyclic ring of 5- or 
6-membered ring is exemplified by those recited for the above-mentioned 
hetero ring. 
The protecting group at the N-terminal in amino acid chemistry is 
specifically methoxybenzoyl, methoxyphenylbutyryl, tert-butyryl and the 
like. 
The amino acid of "acyl of an amino acid" is exemplified by proline, 
sarcosine, pyroglutamic acid and the like; and the protecting group at the 
N-terminal of "acyl of an amino acid having a protecting group at the 
N-terminal" is exemplified by p-toluenesulfonyl, benzyloxycarbonyl, 
benzyloxysuccinyl, succinyl and the like. The amino acid of "acyl of an 
amino acid having a protecting group at the N-teriinal" is exemplified by 
N-benzyloxycarbonylproline, N-benzyloxysuccinylproline, 
N-p-toluenesulfonylsarcosine, N-benzyloxycarbonylsarcosine, 
N-benzyloxy-succinylsarcosine, N-succinylsarcosine, 
N-benzyloxycarbonylpyroglutamine, N-benzyloxysuccinylpyroglutamine, 
N-succinylpyroglutamine and the like. 
The halogen atom, lower alkyl and lower alkoxy of "phenyl which may be 
substituted by at least one substituent selectd from the group consisting 
of a halogen atom, a lower alkyl and a lower alkoxy" are each as defined 
above. 
The aryl of "optionally substituted aryl" is specifically condensed or 
noncondensed aromatic hydrocarbon group such as phenyl, naphthyl and 
indanyl, which may be partly hydrogenated or saturated on demand, such as 
indanyl and 1,2,3,4-tetrahydronaphthyl. 
The heteroaryl of "optionally substituted heteroaryl" is specifically an 
optionally condensed 5- or 6-membered hetero ring having hetero atom such 
as nitrogen atom and sulfur atom. Examples thereof include thienyl, furyl, 
pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, isothiazolyl, oxazolyl, 
isoxazolyl, furazanyl, pyridyl, pyrazinyl, pyrimidinyl, benzofuranyl, 
2,3-dihydrobenzofuranyl, benzothienyl, indolyl, chromenyl, chromanyl, 
quinolinyl, isoquinolinyl and the like. 
The substituent of "optionally substituted aryl or optionally substituted 
heteroaryl" is exemplified by lower alkyl (as defined above), lower alkoxy 
(as defined above), halogen atom (as defined above) and the like. 
The carboxyl-protecting group may be any protecting group as long as it is 
generally used for protecting carboxyl group, and is exemplified by alkyl 
such as methyl, ethyl, propyl, isopropyl, butyl and isobutyl; 
halogen-substituted alkyl such as 2,2,2-trichloroethyl and 
2,2,2-trifluoroethyl; aralkyl such as benzyl, p-methoxybenzyl, 
3,4-dimethoxybenzyl, o-nitrobenzyl, p-nitrobenzyl, p-bromobenzyl, 
diphenylmethyl and trityl; silyl such as trimethylsilyl, triethylsilyl, 
isopropyldimethylsilyl, tert-butyldimethylsilyl, di-tert-butylmethylsilyl, 
phenyldimethylsilyl and tert-butyldiphenylsilyl; and the like. 
The "lower alkyl ester group" is specifically methoxycarbonyl, 
ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl, 
isobutoxycarbonyl, sec-butoxycarbonyl, tert-butoxycarbonyl and the like. 
The substituent of "substituted phenyl" is exemplified by alkyl having 1 to 
9 carbon atoms, benzyl, phenethyl, lower alkenyl, styryl, hydroxy, 
benzyloxy, phenoxy, acyl, halogen atom and the like. The substituent of 
"substituted phenoxy" is exemplified by those recited as the substituent 
for substituted phenyl. 
The "arylalkyloxy having 7 to 9 carbon atoms" is exemplified by benzyloxy, 
phenethyloxy, phenylpropoxy and the like. 
The alkyl or alkoxy having 1 to 4 carbon atoms of "a carbon ring or hetero 
ring which is unsubstituted or substituted by 1 to 3 member(s) selected 
from alkyl, alkoxy having 1 to 4 carbon atoms, nitro and trifluoromethyl" 
is exemplified by the above-mentioned lower alkyl and lower alkoxy having 
1 to 4 carbon atoms. The carbon ring may be, for example, benzene, 
naphthalene, indene, azulene, fluorene, phenanthrene, anthracene, 
acenaphthalene, biphenylene rings and these rings partly or entirely 
saturated; heterocycle may be, for example, furan, thiophene, pyrrole, 
oxazole, isoxazole, thiazole, isothiazole, imidazole, pyrazole, furazan, 
pyran, pyridine, pyridazine, pyrimidine, pyrazine, indole, isoindole, 
benzofuran, benzothiophene, indolizine, chromene, quinoline, isoquinoline, 
quinolizine, purine, indazole, quinazoline, cinnoline, quinoxaline, 
phthalazine, pterin,carbazole, acridine, phenanthridine, xanthene, 
phenazine, phenothiazine and these rings partly or entirely saturated. 
The compound having a prolyl endopeptidase inhibitory activity, which is 
suitably used in the present invention, namely, 
(2S)-1-benzylaminocarbonyl-[(2S)-2-glycolylpyrrolidinyl]-2-pyrrolidinecarb 
oxamide, has the following formula. 
##STR36## 
While the dose of the compound having prolyl endopeptidase inhibitory 
activity to be administered in the present invention varies depending on 
age, body weight, symptom, therapeutic effect, kind of compound, 
administration route and the like, it is, in the case of the compound of 
the formula [I], 1 mg-100 mg per dose for an adult by oral administration 
once to several times a day, or 0.2 mg-20 mg per dose for an adult by 
parenteral administration once to several times a day. 
This compound having prolyl endopeptidase inhibitory activity is used in 
the dosage form of a solid composition or liquid composition for oral 
administration; or an injection, suppository or the like for parenteral 
administration. 
The solid composition for oral administration includes tablet, capsule, 
powder, granule and the like. One or more active ingredient(s) is/are 
admixed with at least one pharmaceutically acceptable inert diluent to 
give a solid composition. Where necessary, excipient, binder, lubricant, 
disintegrator, solubilizing agent, stabilizer and the like may be added. A 
capsule includes hard capsule and soft capsule. 
The liquid composition for oral administration includes solution, emulsion, 
suspension, syrup, elixir and the like. The liquid composition contains 
conventional inert pharmaceutically acceptable diluents. It may also 
contain auxiliary agent (e.g., moistening agent), suspending agent, 
sweetener, flavor, aromatic and preservative. 
The injection for parenteral administration may be, for example, sterile 
aqueous or nonaqueous solution, suspension, emulsion and the like. The 
injection contains one or more active ingredient(s) admixed with at least 
one pharmaceutically acceptable inert aqueous diluent, pharmaceutically 
acceptable inert nonaqueous diluent, and the like. Where necessary, 
antiseptic, moistening agent, emulsifying agent, dispersing agent, 
stabilizer, solubilizing agent and the like may be added. They are 
generally sterilized by filtration using a bacteria preserving filter and 
the like, addition of antimicrobial agents or irradiation of .gamma.-ray. 
Alternatively, after these treatments, the liquid composition is prepared 
into a solid composition by lyophilization and the like, and diluted 
immediately before use with sterile water, sterile diluent for injection 
and the like. 
The present invention is explained in more detail by illustrative Examples, 
to which the present invention is not limited. 
EXAMPLE 1 
Time Course Changes in Plasma Cholinesterase Activity After Single Oral 
Administration 
Male SD rats (7 weeks of age, Japan Charles River, 5 per group) were orally 
administered with 
(2S)-1-benzylaminocarbonyl-[(2S)-2-glycolylpyrrolidinyl]-2-pyrrolidinecarb 
oxamide (1000 mg/kg) suspended in 0.5% aqueous sodium 
carboxymethylcellulose solution (5 ml/kg). To the control group was orally 
administered 0.5% aqueous sodium carboxymethylcellulose solution (5 
ml/kg). One hour, 24 hours, 2 days, 3 days, 10 days and 18 days later, the 
rats were opened in abdomen under light ether anesthesia, and blood 
samples were taken from the aorta into heparin-treated tubes using a blood 
collection needle. The blood was centrifuged for 15 min at 3000 r.p.m. and 
the obtained plasma was subjected to determination of cholinesterase 
activity according to the DTNB method of Ellman (Biochem. Pharmacol., 7, 
88-95 (1961)). The activity was determined using 7.0 mM butyrylthiocholine 
iodide as a substrate. For the determination, a spectrophotometer was used 
and released thiocholine was determined by the rate assay at wavelength of 
412 nm. Changes in plasma cholinesterase activity at 1 hour, 24 hours, 2 
days, 3 days, 10 days and 18 days after the administration are shown in 
FIG. 1. The cholinesterase activity of the group administered with the 
test compound elevated about 1.8 times that of control at 24 hours after 
administration and reached about 2.3 times that of control at 2 days after 
administration. The cholinesterase activity gradually decreased from 3 
days postadministration to the same level with the control at 18 days 
postadministration. 
EXAMPLE 2 
Dose Dependency of Plasma Cholinesterase Activity After Single Oral 
Administration 
Male SD rats (6 weeks of age, Japan Charles River, 5 per group) were orally 
administered with 
(2S)-1-benzylaminocarbonyl-[(2S)-2-glycolylpyrrolidinyl]-2-pyrrolidinecarb 
oxamide (1, 3, 10, 30 and 100 mg/kg) suspended in 0.5% aqueous sodium 
carboxymethylcellulose solution (5 ml/kg). To the control group was orally 
administered 0.5% aqueous sodium carboxymethylcellulose solution (5 
ml/kg). In the same manner as in Example 1, the plasma cholinesterase 
activity was determined at 3 days postadministration. The results are 
shown in FIG. 2. The cholinesterase activity showed significant increase 
by the administration of 30 mg/kg to 100 mg/kg of the test compound, and 
the activity elevated in a dose-dependent manner in the group administered 
with 30 mg/kg to 100 mg/kg of the test compound. 
EXAMPLE 3 
Changes of Plasma Cholinesterase Activity After Repeated Administration for 
7 Days 
To male SD rats (10 weeks of age, Japan Charles River, 4 per group) was 
orally administered, once a day for consecutive 7 days, 
(2S)-1-benzylaminocarbonyl-[(2S)-2-glycolylpyrrolidinyl]-2-pyrrolidinecarb 
oxamide (100 mg/kg) suspended in 0.5% aqueous sodium carboxymethylcellulose 
solution (5 ml/kg). At 24 hours after the final administration, the rats 
were sacrificed in the same manner as in Example 1, whereby test samples 
were obtained. To the control group was orally administered 0.5% aqueous 
sodium carboxymethylcellulose solution (5 ml/kg). The respective 
cholinesterase activities are shown in FIG. 3. The cholinesterase activity 
increased 2.7 times as that of the control. 
EXAMPLE 4 
Time Course Changes in Plasma Cholinesterase activity After Single 
Intravenous Administration 
To male SD rats (6 weeks of age, Japan Charles River, 5 per group) was 
intravenously administered, from the tail vein, 
(2S)-1-benzylaminocarbonyl-[(2S)-2-glycolylpyrrolidinyl]-2-pyrrolidinecarb 
oxamide (100 mg/kg) dissolved in physiological saline for injection (2.5 
ml/kg). To the control group was intravenously administered, from the tail 
vein, physiological saline for injection (2.5 ml/kg). The rats were 
sacrificed in the same manner as in Example 1 at 1 hour, 6 hours, 24 
hours, 2 days and 3 days later to obtain test samples, which were 
subjected to the determination of cholinesterase activity. The results are 
shown in FIG. 4. The cholinesterase activity started to increase from 24 
hours postadministration and continued to increase with the passage of 
time for 3 days after administration. 
EXAMPLE 5 
Effects of Repeated Administration for 5 Days on the Metabolism of Cocaine 
(1) Sample Preparation 
To male ICR mice (10 weeks of age, Japan Clea, 11-15 per group) was orally 
administered, once a day for consecutive 5 days, 
(2S)-1-benzylaminocarbonyl-[(2S)-2-glycolylpyrrolidinyl]-2-pyrrolidinecarb 
oxamide (100 mg/kg) dissolved in water (2.5 ml/kg). Control group was 
orally administered with physiological saline (2.5 ml/kg). At 5 minutes 
after the final administration of the test compound and saline, 20 mg/kg 
(10 ml/kg saline) of cocaine was intraperitoneally administered. The blood 
was taken by cervical incision at 30, 60, 120 and 240 minutes after 
administration. A small amount of eserine was added in advance into the 
blood sampling tube to prevent decomposition of cocaine after blood 
sampling. The blood was centrifuged immediately at 4.degree. C. to give a 
serum. To each serum (0.2-0.4 ml) was added 200 ng of lidocaine as the 
internal standard. Then, cocaine and its metabolites (benzoylecgonine, 
ecgonine methylester and norcocaine) were extracted. The standard product 
of the metabolite was prepared by hydrolysis or demethylation of cocaine. 
The cocaine and its metabolite were extracted as follows. For 
deprotenization, 0.5 M HClO.sub.4 (2 ml) was added to the serum containing 
with lidocaine, and the mixture was centrifuged at 3000 rpm for 10 
minutes. The upper layer was washed with ethyl ether, and the aqueous 
layer was made alkaline with 1 M NH.sub.4 OH, which was followed by 
extraction with 7 ml of CH.sub.2 Cl.sub.2 /2-propanol (9:1). The solvent 
was removed from the resulting organic layer under nitrogen atmosphere, 
and the organic layer was treated with 220 .mu.l of pentafluoropropionic 
anhydride (PFP)/2,2,2-trifluoroethanol (TFE)/ethyl acetate (10:2:10) at 
80.degree. C. for 30 minutes, which was followed by evaporation of the 
solvent under nitrogen atmosphere. To the obtained residue was added 80 
.mu.l of toluene/heptane/iso-amyl alcohol (75:20:5) and 50 pl of 0.5 M 
phosphate buffer (pH 8.5), and the mixture was admixed by stirring. 
Centrifugation gave an organic layer containing cocaine and its 
metabolites. 
The obtained organic layer (3 .mu.l) was analyzed with a mass spectrometer 
directly connected to gas chromatography. The analysis conditions were as 
follows. 
apparatus; HP 5890 II GC/HP 5972 MSD 
column; HP-5, 30 m.times.0.25 mm, 0.25 .mu.m film 
temperature; injection port: 260.degree. C., detector: 280.degree. C. 
oven: 100.degree. C. (1 min) programmed to 270.degree. C. (5 min) at 
20.degree. C./min He pressure; constant flow after 25.2 psi for 0.5 min to 
10.6 psi at 99.0 psi/min 
electron energy; 70 ev 
monitoring ions m/z 86: lidocaine 
m/z 250, 413: ecgonine-O-PFP, O-TFE 
m/z 182, 345: ecgonine methylester-O-PFP 
m/z 250, 371: benzoylecgonine-O-TFE 
m/z 182, 303: cocaine 
m/z 313, 105: norcocaine-N-PFP 
(2) Results 
The determination results of the contents of cocaine and its metabolites 
are shown in FIG. 5. 
The concentration of non-metabolized cocaine of the group administered with 
(2S)-1-benzylaminocarbonyl-[(2S)-2-glycolylpyrrolidinyl]-2-pyrrolidinecarb 
oxamide was significantly lower than that of the control group, as 
determined at 30 minutes after cocaine administration. While no statistic 
significance was observed, the benzoylecgonine concentration at 30 minutes 
after cocaine administration was also lower in the group administered with 
(2S)-1-benzylaminocarbonyl-[(2S)-2-glycolylpyrrolidinyl]-2-pyrrolidinecarb 
oxamide. 
EXAMPLE 6 
Effects on Cocaine-induced Spontaneous Locomotion 
To male ICR mice (10 weeks of age, Japan Clea, 13 per group) was orally 
administered, once a day for consecutive 5 days, 
(2S)-1-benzylaminocarbonyl-[(2S)-2-glycolylpyrrolidinyl]-2-pyrrolidinecarb 
oxamide (100 mg/kg) dissolved in water (2.5 ml/kg). Saline (2.5 ml/kg) was 
orally administered to the control group. The treated mice were stabilized 
in a determination cage for 30 minutes, and cocaine was intraperitoneally 
administered according to Example 5. As placebo, saline was 
intraperitoneally administered instead of cocaine. The amount of 
spontaneous locomotion in one hour after administration was determined by 
SCANET (Toyo Industry) and detected by the "two-way analysis of variance 
with repeated measures on one factor" method. 
The group treated with 
(2S)-1-benzylaminocarbonyl-[(2S)-2-glycolylpyrrolidinyl]-2-pyrrolidinecarb 
oxamide showed a significant decrease by half of the increase in 
spontaneous locomotion induced by cocaine. A temporary increase in 
locomotion was found in the placebo groups, but no difference was found 
between the group treated with the test compound and the control group. 
The results were in harmony with the results obtained in Example 5, 
wherein serum cocaine concentration was lower than that of the control 
group for 1 hour after the administration of 
(2S)-1-benzylaminocarbonyl-[(2S)-2-glycolylpyrrolidinyl]-2-pyrrolidinecarb 
oxamide. 
As is evident from the foregoing Examples, a compound having a prolyl 
endopeptidase inhibitory activity significantly increases cholinesterase 
activity in the body. Thus, such compound can be beneficially used for the 
treatment of patients suffering from cocainism.