Sankyo Company, Limited

Yuichiro Yabe

Tatsuo Kokubu

Kunio Hiwada

Hiroyuki Koike

Yasuhiro Morisawa

Mitsuru Kataoka

Yasuteru Iijima

Hidekuni Takahagi

Mitsuo Yamazaki

Yoshihiko Baba

Rei Matsueda

Hiroshi Handa

Susumu Higashida

Atsushi Hattori

Tomoaki Komai

Seigo Ueda

Yutaka Okada

Mitsuya Sakurai

Takashi Nishigaki

Hiroyashi Horikoshi

Sadamasa Minato

Compounds of formula (I): ##STR1## wherein: R.sup.1 is hydrogen, alkyl, aralkyl, --COR.sup.a, --COR.sup.b, --CSR.sup.a, --CSR.sup.b, --SO.sub.2 R.sup.b, --CONHR.sup.b, --CSNHR.sup.b, --CONR.sup.b R.sup.b or --CSNR.sup.b R.sup.b ; R.sup.2 is hydrogen or alkyl; R.sup.3 is hydrogen, alkylidene, substituted alkyl, or R.sup.b ; R.sup.4 is optionally substituted alkyl, cycloalkyl, or aryl; R.sup.5 is R.sup.b O--, R.sup.b R.sup.b N--, R.sup.b HN--, aralkyloxycarbonyloxy or aralkyloxycarbonylamino, or R.sup.5 is --(CH.sub.2).sub.p --D--(CH.sub.2).sub.r --, where D is a single bond, carbonyl, oxygen, sulfur, --NH--, --(CH.sub.2 .dbd.CH.sub.2)-- or --NHCO--; and p and r are each 0 or an integer from 1 to 5; A is --(CH.sub.2).sub.m --B--(CH.sub.2).sub.n -- where B is a single bond, carbonyl, oxygen, sulfur, --NH--, --(CH.sub.2 .dbd.CH.sub.2)-- or --NHCO--; and m and n are each 0 or an integer from 1 to 5; R.sup.a is alkoxy, aralkyloxy, aryloxy or alkoxycarbonyl; R.sup.b is optionally substituted alkyl, cycloalkyl, heterocyclic, aryl or arylalkenyl; and pharmaceutically acceptable salts and esters thereof and pro-drugs therefor, have the ability to inhibit the activity of HIV protease and may thus be used for the treatment and prophylaxis of AIDS.

Inhibitors of HIV protease

Oligopeptides of formula (I): ##STR1## where R.sup.1 -R.sup.5 are various organic groups, and A represents a group of formula --NH-- or --(CH.sub.2).sub.n --, in which n represents an integer of from 1 to 3, have renin-inhibitory activity and are particularly suitable for oral administration. They may be prepared by condensing their component amino acids or lower oligopeptides using conventional peptide synthesis reactions.

New renin-inhibitory oligopeptides, their preparation and their use

Compounds of formula (I): ##STR1## [in which: R.sup.1 is heterocyclic group having 5 or 6 ring atoms, or --NR.sup.7 R.sup.8, where R.sup.7 is alkyl and R.sup.8 is optionally substituted phenyl, optionally substituted phenylalkyl or cycloalkyl; R.sup.2 is optionally substituted phenyl or naphthyl; R.sup.3 is thiazolyl; R.sup.4 is cyclohexyl or isopropyl; R.sup.5 is alkyl; and R.sup.6 is alkyl] and salts thereof have renin-inhibitory and, hence, hypotensive activities and are of value in the diagnosis and treatment of hypertension induced by failures in the renin-angiotensin system. They may be prepared by reacting together appropriate amino acids or derivatives thereof.

Peptides having renin inhibitory activity, their preparation and use

Compounds of formula (I): ##STR1## A is a carbon-carbon bond or C.sub.1 -C.sub.3 alkylene; B is imino group or C.sub.1 -C.sub.2 alkylene; R.sup.1 is C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, heterocyclic or optionally substituted amino; R.sup.2 is optionally substituted phenyl or optionally substituted naphthyl; R.sup.3 is thiazolyl, isoxazolyl or imidazolyl; R.sup.4 is isopropyl or cyclohexyl; R.sup.5 and R.sup.6 are C.sub.1 -C.sub.4 alkyl, or, together with the carbon atom to which they are attached, C.sub.3 -C.sub.7 cycloalkyl; R.sup.7 is hydrogen, optionally substituted C.sub.1 -C.sub.6 alkyl group; and R.sup.8 is hydrogen or C.sub.1 -C.sub.4 alkyl. These compounds have renin-inhibitory and, hence, hypotensive activities. The invention also provides a method for the treatment or prophylaxis of hypertension induced by failures in the renin-angiotensin system.

Renin-inhibitory oligopeptides, their preparation and use

New renin-inhibitory peptides and their use

Oligopeptides of formula (I) ##STR1## (wherein R.sup.1 CO-- is an acyl group. But is an isobutyl or sec-butyl group and X is a variety of organic groups) and salts and esters thereof have valuable renin inhibitory activity.

Hypotensive peptides and their use

Improvement in determination of an enzyme activity in a substance having an enzymatic activity which comprises employing an aromatic primary amine derivative as a substrate and an iron complex treated with a peroxide as a color reagent.

Method for the determination of enzyme activities

Analogs of LH-RH and process for preparing the same

Growing community of inventors

Hiromachi, Japan

Yuichiro Yabe