Abstract: Disclosed are compound of formula I whereinR represents hydrogen, lower alkyl, cycloalkyl, bicycloalkyl, adamantyl, aryl, biaryl, or mono- or di-(cycloalkyl, aryl or biaryl)-lower alkyl, di-(lower alkyl or aryl-lower alkyl)amino-lower alkyl, or (piperidino, morpholino, pyrrolidino)-lower alkyl;R.sub.1 represents hydrogen, lower alkyl, cycloalkyl, aryl, biaryl, or (cycloalkyl, aryl or biaryl)-lower alkyl;R.sub.2 represents hydrogen, lower alkyl, lower alkoxy, aryl-lower alkyl, aryl-lower alkoxy, amino, mono- or di-(lower alkyl or aryl-lower alkyl)-amino, acylamino, or (lower alkyl or aryl-lower alkyl)-(thio, sulfinyl or sulfonyl);R.sub.3 represents hydrogen, lower alkyl, cycloalkyl, aryl-lower alkyl, cycloalkyl-lower alkyl, or C.sub.2 -C.sub.7 -alkyl interrupted by S, SO, SO.sub.2, O or N--R.sub.5 ;R.sub.4 represents hydrogen or acyl;R.sub.

Abstract: 4-Substituted-4-piperidinecarboxamides of Formula I are antagonists of VLA-4 and/or .alpha..sub.4 .beta..sub.7, and as such are useful in the inhibition or prevention of cell adhesion and cell-adhesion mediated pathologies. These compounds may be formulated into pharmaceutical compositions and are suitable for use in the treatment of asthma, allergies, inflammation, multiple sclerosis, and other inflammatory and autoimmune disorders.

Abstract: Novel enzyme-inhibitory compounds are disclosed. The subject invention further pertains to methods and compositions for the inhibition of bacteria, viruses, parasites, and other pathogens.

Abstract: This invention relates to sulfamides of formula (I) ##STR1## that are inhibitors of metalloproteases, pharmaceutical compositions containing them, methods for their use and methods for preparing these compounds.

Abstract: Levobupivacaine or an analogue thereof is prepared by reaction with a tartaric acid resolving agent in a solvent, in the presence of water and/or less 0.5 equivalents of the resolving agent.

Abstract: New compounds of the formula (A) ##STR1## a process for their preparation and their use in the manufacture of pharmaceutical preparations. The new compounds have both local anaesthetic and analgesic effect.

Abstract: New process for the preparation of ropivacaine hydrochloride monohydrate adapted for production in the plant, which process includes three steps.

Abstract: This invention relates to neurotrophic low molecular weight, small molecule N-linked ureas and carbamates of heterocyclic thioesters having an affinity for FKBP-type immunophilins, and their use as inhibitors of the enzyme activity associated with immunophilin proteins, particularly peptidyl-prolyl isomerase, or rotamase, enzyme activity.

Abstract: The present invention relates to compounds of Formula I: ##STR1## that are matrix metalloprotease inhibitors, pharmaceutical compositions containing them, methods for their use and methods of preparing these compounds.

Abstract: The subject invention concerns a compound of formula (X), ##STR1## which can be prepared from the starting material L-lysine, and converted to levobupivacaine by cyclization.

Abstract: This invention relates to peptide derivatives, pharmaceutical formulations containing those compound and methods of their use as thrombin inhibitors.

Abstract: Cyclopropyl derivatives of formula (I) wherein R is cyclopropyl or methyllopropyl are prepared by reaction of 2,6-dibromohexanoyl chloride with 2,6-dimethylaniline in the presence of a base at 0.degree.-25.degree. C. to give 2,6-dibromohexanoyl-2,6-dimethylanilide which subsequently is reacted with R--NH.sub.2 (wherein R is cyclopropyl or methylcyclopropyl) at 70.degree.-100.degree. C. The compounds are useful as antiarrhythmic agents and as local anaesthetic agents.

Abstract: HIV protease inhibitors, obtainable by chemical synthesis, inhibit or block the biological activity of the HIV protease enzyme, causing the replication of the HIV virus to terminate. These compounds, as well as pharmaceutical compositions that contain these compounds and optionally other anti-viral agents as active ingredients, are suitable for treating patients or hosts infected with the HIV virus, which is known to cause AIDS.

Abstract: Compounds represented by the structural formula ##STR1## or a pharmaceutically acceptable salt thereof are disclosed, wherein: A.sup.1 is --CH.sub.2 R.sup.6, --OR.sup.6, --N(R.sup.6)(R.sup.7), --S(O).sub.e R.sup.13, --(C(R.sup.6)(R.sup.7)).sub.1-6 --OR.sup.6, --(C(R.sup.6)(R.sup.7).sub.1-6 --N(R.sup.6)(R.sup.7) or --(C(R.sup.6) (R.sup.7)).sub.1-6 --S(O).sub.e R.sup.13 and A.sup.2 is H, or A.sup.1 and A.sup.2 together are .dbd.O, .dbd.C(R.sup.6)(R.sup.7), .dbd.NOR.sup.6 or .dbd.S;Q is phenyl, naphthyl, --SR.sup.6, --N(R.sup.6)(R.sup.7), --OR.sup.6 or heteroaryl;T is H, aryl, heterocycloalkyl, heteroaryl, cycloalkyl or bridged cycloalkyl;b is 0, 1 or 2;b.sub.1 is 1 or 2;X is a bond, --C(O)--, --O--, --NR.sup.6 --, --S(O).sub.e --, --N(R.sup.6)C(O)--, --C(O)N(R.sup.6)--, --OC(O)NR.sup.6 --, --OC(.dbd.S)NR.sup.6 --, --N(R.sup.6)C(.dbd.S)O--, --C(.dbd.NOR.sup.6)--, --S(O).sub.2 N(R.sup.6)--, --N(R.sup.6)S(O).sub.2 --, --N(R.sup.6)C(O)O-- or --OC(O)--;R.sup.6, R.sup.7, R.sup.8a, and R.sup.

Abstract: A process for the racemisation of an optically-enriched piperidine-2-carboxanilide compound, comprises heating the compound in the presence of an alkanoic or arylalkanoic acid. A process for the asymmetric transformation of such a compound comprises heating the compound in the presence of an acid as defined above, a chiral acid resolving agent and an inert cosolvent.

Abstract: The present invention is concerned with diaryl compounds of formula (l) and their use in medical therapy, particularly in the prophylaxis or treatment of a clinical condition for which an ACAT inhibitor is indicated, such as hyperlipidaema or atherosclerosis. The invention also relates to pharmaceutical compositions and processes for the preparation of compounds according to the invention.

Abstract: A process for preparing levobupivacaine, racemic bupivacaine or another N-alkyl analogue thereof, comprises chlorinating pipecolic acid hydrochloride, amidation of the resultant pipecolyl chloride hydrochloride in solvent, without isolation, with 2,6-dimethylaniline, and alkylation of the resultant pipecolic acid 2,6-xylidide. Alternatively, the alkylation may be followed by the amidation.

Abstract: The present invention discloses a new and improved process for the preparation of sameridine and its pharmaceutically acceptable salt.

Abstract: New compounds of the formula (A) ##STR1## a process for their preparation and their use in the manufacture of pharmaceutical preparations. The new compounds have both local anaesthetic and analgesic effect.

Abstract: A substituted cyclic amine compound represented by the following general formula (1) ##STR1## wherein each of R.sup.1 to R.sup.5 represents a hydrogen atom, a halogen atom, a lower alkyl group, a lower alkoxy group or the like, A represents a carbonyl group or a sulfonyl group, B represents a methine moiety or a nitrogen atom, D represents a methine moiety, a nitrogen atom or .dbd.N(.fwdarw.O)-- and n is an integer of 2 to 3; and synthetic methods thereof. The inventive compound is useful in preventing and treating circulatory organ-related diseases such as hypertension, ischemic heart disease, cerebrovascular disease, peripheral circulatory disease and the like.

Abstract: The invention relates to new arylglycinamide derivatives of general formula I ##STR1## and the pharmaceutically acceptable salts thereof, wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and Ar have the meanings given in the specification, and the preparation and use thereof. The new compounds are valuable neurokin (tachykinin) antagonists.

Abstract: Compounds which suppress human T-lymphocyte proliferation are disclosed.

Abstract: Novel tricyclic triazolo derivatives and pharmaceutically acceptable salts thereof, which are useful as anti-inflammation agents, anti-allergy agents or anti-PAF agents as well as processes for producing the same are disclosed. The triazolo derivatives of the present invention are represented by the formula (I): ##STR1## ?wherein R.sup.1 represents hydrogen, lower alkyl or C.sub.3 -C.sub.5 cycloalkyl; R.sup.2 and R.sup.3 respectively represent hydrogen, lower alkyl, lower alkoxy or halogen; W represents C.dbd.O or CR.sup.4 R.sup.5 (wherein R.sup.4 and R.sup.5 respectively represents hydrogen or lower alkyl); A represents C.sub.1 -C.sub.5 straight or branched saturated or unsaturated alkylene which may contain one or more hetero atoms; l represents 0 to 2, n represents 1 to 3, . . . represents single bond or double bond; Y represents N or C; Z represents C(B)Ar.sup.1 Ar.sup.2 (wherein B represents hydrogen, hydroxy or methoxy, Ar.sup.1 and Ar.sup.

Abstract: Fused tricyclic heteroaromatic compounds of formula ##STR1## wherein one of X and Y represents nitrogen, and the other of X and Y represents oxygen, sulphur or N--R.sup.2 ;Q represents a substituted five- or six-membered monocyclic heteroaliphatic ring which contains one nitrogen atom as the sole heteroatom and is linked to the five-membered heteroatomic ring containing the moieties X and Y via a carbon atom: as well as substituted 3,4-dihydro-1-hydroxy-2-oxomethyl-naphthalene precursors thereto, are ligands for dopamine receptor subtypes within the body and are therefore useful in the treatment of disorders of the dopamine system, in particular schizophrenia.

Abstract: This invention relates to certain novel compounds and derivatives thereof, their synthesis, and their use as selective alpha-1a adrenergic receptor antagonists. One application of these compounds is in the treatment of benign prostatic hyperplasia. These compounds are selective in their ability to relax smooth muscle tissue enriched in the alpha 1a receptor subtype without at the same time inducing orthostatic hypotension. One such tissue is found surrounding the urethral lining. Therefore, one utility of the instant compounds is to provide acute relief to males suffering from benign prostatic hyperplasia, by permitting less hindered urine flow. Another utility of the instant compounds is provided by combination with a human 5-alpha reductase inhibitory compound, such that both acute and chronic relief from the effects of benign prostatic hyperplasia are achieved.

Abstract: Novel aminoalkyloximes, precursors and processes for the preparation thereof, and methods of treating depression and obsessive compulsive disorders are described.

Abstract: 1-Acylpiperidine compound of the formula I ##STR1## in which R.sub.1 is an optionally substituted aralkyl, aryloxyalkyl, heteroaralkyl, aroyl, heteroaroyl, cycloalkylcarbonyl, aralkanoyl, heteroarylalkanoyl, aralkoxycarbonyl or arylcarbamoyl radical or the acyl radical of an .alpha.-amino acid which is optionally N-substituted by lower alkanoyl or carbamoyl-lower-alkanoyl, R.sub.2 is cycloalkyl or an optionally substituted aryl or heteroaryl radical, R.sub.3 is hydrogen, alkyl, carbamoyl or an alkanoyl or alkenoyl radical which is optionally substituted by carboxyl or esterified or amidated carboxyl, R.sub.4 is an optionally substituted aryl or optionally partially hydrogenated heteroaryl radical, X.sub.1 is methylene, ethylene, a direct linkage, an optionally ketalized carbonyl group or an optionally etherified hydroxymethylene group, X.sub.2 is alkylene, carbonyl or a direct linkage, and X.sub.

Abstract: Compounds of formula I ##STR1## wherein R.sub.1 is a 2-R.sub.A -3-R.sub.B -phenyl radical, a 2-R.sub.A -4-R.sub.C -phenyl radical, a 2-R.sub.A -pyridin-3-yl radical, a 3-R.sub.A -pyridin-2-yl radical or a 1-R.sub.D -indol-3-yl radical, wherein one of the radicals R.sub.A and R.sub.B is an aliphatic or heterocycloaliphatic-aliphatic radical or free or aliphatically, araliphatically or heteroaraliphatically etherified hydroxy and the other is hydrogen, an aliphatic radical or free or esterified or amidated carboxy, R.sub.C is hydrogen, an aliphatic radical, free or aliphatically, araliphatically, heteroaraliphatically or heteroarylaliphatically etherified hydroxy or an unsubstituted or heteroaliphatically substituted amino group, and R.sub.D is an aliphatic, araliphatic or heteroaliphatic radical, one of the radicals X.sub.1 and X.sub.2 is carbonyl and the other is methylene, R.sub.2 is an aliphatic radical, R.sub.3 is unsubstituted or aliphatically substituted amino, R.sub.

Abstract: A compound of the formula (I) or (II): ##STR1## where R.sup.1, R.sup.2, R.sup.5 and R.sup.6 are the same or different and represent a hydrogen atom or a halogen atom and R.sup.1 and R.sup.2 may combine to form a ring; R.sup.3, and R.sup.4 are the same or different and represent a hydrogen atom, a halogen atom, a benzoyl group, a group of the formula --L(CH.sub.2).sub.n R.sup.8 where n is 1 to 8, R.sup.8 is a hydrogen, hydroxy, amino, dialkylamino, --COR.sup.16 or --COOR.sup.14 where R.sup.16 is a hydrogen, chlorine, COCl, C.sub.1 -C.sub.8 alkyl, --NR.sub.2 or aryl and R.sup.14 is a hydrogen, C.sub.1 -C.sub.8 alkyl, aryl, COR, 2,4-dinitrophenyl, N-imido or --NR.sub.2 and L is a direct bond or C.dbd.O; W is .dbd.O; W.sup.1 is hydrogen or --OR.sup.9, where R.sup.9 is hydrogen, C.sub.1 -C.sub.8 alkyl, acyl or a group of the formula --(CH.sub.2).sub.n R.sup.10 where n is 1 to 8 and R.sup.10 is amino, dialkylamino, hydroxy, acryloyl or methacryloyl; Y is oxygen, sulfur, selenium, tellurium, C.dbd.O, or >N--R.

Abstract: A compound of the formula (I): ##STR1## or a pharmaceutically acceptable salt thereof is disclosed, as well as processes for and intermediates in the preparation thereof, and a method of antagonizing endothelin.

Abstract: A compound represented by the general formula (I) and a pharmaceutically acceptable salt and solvate thereof having an effect for inhibiting the agglutination of platelets is disclosed: ##STR1## wherein R.sup.1 represents a group --W--(CH.sub.2).sub.i --COOR.sup.3,R.sup.2 represents a hydrogen atom or a group --W--(CH.sub.2).sub.i --COOR.sup.3 or --OR.sup.4,X represents --CH.dbd. or --N.dbd.,Y represents(i) a group --(CO).sub.k --N(R.sup.5)--Z--, wherein Z represents a bond or a group --(CH.sub.2).sub.m --CO-- or a group --(CH.sub.2).sub.m --CHR.sup.6 --,(ii) a group --(CH.sub.2).sub.m --N(R.sup.5)--(CO).sub.k --, or(iii) a group --(CO).sub.k -Het, wherein Het represents a five- or six-membered heterocyclic ring comprising a nitrogen atom,A represents(i) the following groups (III) or (IV) ##STR2## B represents a bond, C.sub.1-6 alkylene or C.sub.2-6 alkenylen.

Abstract: Compounds of formula (I): ##STR1## [wherein: R.sup.1 is aryl; R.sup.2 is hydrogen, alkyl, alkoxy, halogen or cyano; R.sup.3 is a group of formula --B--NR.sup.4 R.sup.5, where R.sup.4 and R.sup.5 are independently hydrogen, alkyl or substituted alkyl or R.sup.4 and R.sup.5, together with the nitrogen to which they are attached, form a heterocycle, and B is alkylene or a group of formula --CH.sub.2 CH(OR.sup.6)CH.sub.2 --, where R.sup.6 is hydrogen, alkanoyl, substituted alkanoyl or arylcarbonyl, or a group of formula --D--R.sup.7, where D is a single bond or alkylene and R.sup.7 is a heterocycle; and A is alkylene; and pharmaceutically acceptable salts and esters thereof] are useful for the treatment and prevention of circulatory diseases and psychosis.

Abstract: Compositions containing compounds ##STR1## and their pharmaceutically acceptable acid addition salts inhibit proteases of viral origin and can be used as medicaments for the treatment or prophylaxis of viral infections. They can be manufactured according to generally known procedures.

Abstract: The invention is directed to a new class of antiarrhythmic agents of the formula: ##STR1## in which R is represented by hydrogen, halogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy, CF.sub.3, SR.sub.1, NHC(O)R.sub.2, NH.sub.2, or OH; R.sub.1 is hydrogen or C.sub.1-4 alkyl; R.sub.2 is C.sub.1-4 alkyl; X is represented by CO or CHOH; R.sub.3 and R.sub.4 are each independently represented by methyl, ethyl, n-propyl, or R.sub.3 and R.sub.4 together with the carbon atom to which they each are attached form a C.sub.5 or C.sub.6 cycloalkyl; and Alk is a C.sub.1-4 alkyl; or a pharmaceutically acceptable addition salt thereof.

Abstract: The invention relates to novel S-nitroso derivatives of ACE inhibitors and to pharmaceutical compositions comprising the S-nitrosothiol derivatives of the invention together with a pharmaceutically acceptable carrier.The invention also relates to methods for treating various pathophysiological conditions including acute myocardial infarction, left ventricular dysfunction without overt heart failure, hypertension, pulmonary hypertension, congestive heart failure, angina pectoris, vascular thrombosis, Raynauds syndrome, scleroderma, toxemia of pregnancy, acute renal failure, diabetic nephropathy, and renal artery stenosis, and to methods of inhibiting ACE and effecting vasodilation comprising administering the S-nitrosothiol derivatives of the ACE inhibitors of the invention to an animal.

Abstract: An imide compound of the formula: ##STR1## wherein Z is a group of the formula: ##STR2## in which the substituents are defined herein, and n is an integer of 0 to 1;D is a group of the formula:--(CH.sub.2).sub.p --A--(CH.sub.2).sub.q --in which A is a non-aromatic hydrocarbon ring optionally bridged with a lower alkylene group or an oxygen atom, said non-aromatic hydrocarbon ring and said lower alkylene group being each optionally substituted with at least one lower alkyl, and p and q are each an integer of 0, 1 or 2; andAr is an aromatic group, a heterocyclic aromatic group, a benzoyl group, a phenoxy group or a phenylthio group and G is >N--, >CH-- or >COH-- or Ar is a biphenylmethylidene group and G is >C.dbd., all of the above groups being each optionally substituted with at least one of lower alkyl, lower alkoxy and halogen; and its acid addition salts, useful as an antipsycotic agent.

Abstract: This invention relates to substituted dihydroxypropylamines, a process to prepare intermediates useful for the synthesis of these compounds, compositions comprising such compounds, and a method of treating retroviral infection.

Abstract: The present invention is direct to a new class of 1-piperidinyl alkanoarylsulfonamides of the formula I ##STR1## wherein R, X, m, n, and Alk are defined in the specification, and their use as antiarrhythmic agents.

Abstract: Dioxobutanoic acids substituted with piperidine or similar N-substituted saturated cycloalkyls are found to inhibit the cap-dependent endonuclease of influenza virus. These compounds are useful in the prevention or treatment of infection by influenza virus and the treatment of influenza, either as compound, pharmaceutically acceptable salts,. pharmaceutical composition ingredients, whether or not in combination with other antivirals, immunomodulators, antibiotics or vaccines. Methods of treating influenza and methods of preventing or treating infection by influenza virus are also described.

Abstract: A synthetic polyamide of formula I and its salts ##STR1## in which each R.sub.1 independently is selected from hydrogen, carboxyl, amino or a group of formula .alpha.-A.sub.1 -R.sub.10 (.alpha.)where A, is a bridging group and R.sub.10 is a sterically hindered amine group;each R.sub.2 independently is hydrogen or a group of formula .alpha.A is a bridging group of the formula ##STR2## is 0 or 1; R.sub.3 is hydrogen, C.sub.1-12 alkyl or is a significance of R.sub.10 ;R.sub.5 is hydrogen or C.sub.1-12 alkylR.sub.4 is a significance of R.sub.10 or a group of formula .alpha.; andp is an integer from 5 to 200;with the proviso that the compound of formula I contains 1-400 sterically hindered amine groups.

Abstract: Compounds of the formula ##STR1## wherein and their pharmaceutically acceptable acid addition salts inhibit proteases of vital origin and can be used as medicaments for the treatment or prophylaxis of viral infections. They can be manufactured according to generally known procedures.

Abstract: Esters and amides of aminomethylenecyanoacetic acid I ##STR1## where R.sup.1 and R.sup.2 are each, independently of one another, phenyl, naphthyl, biphenylyl or five- or six-membered hetaryl with one, two or three nitrogens or one oxygen or one sulfur or one nitrogen and one oxygen or one nitrogen and one sulfur, which can be benzo-fused, it being possible for these radicals to be substituted by one to three C.sub.1 -C.sub.12 -alkyl groups, C.sub.1 -C.sub.12 -alkoxy groups, halogen atoms, cyano groups, hydroxyl groups or groups of the formulae COOR.sup.3, COR.sup.3, CONHR.sup.3, OCOR.sup.3 or NHCOR.sup.3, and whereR.sup.3 is C.sub.1 -C.sub.12 -alkyl, C.sub.5 -C.sub.8 -cycloalkyl or phenyl,X is C.sub.2 -C.sub.30 -alkylene which can be interrupted by non-adjacent oxygens, or is C.sub.4 -C.sub.12 -alkenylene or C.sub.4 -C.sub.12 -alkynylene where the unsaturated bonds are not adjacent to the ester oxygens, or is C.sub.5 -C.sub.8 -cycloalkylene or phenylene, andY is O or NH.

Abstract: Carboxamide derivatives of the following general formula (I): ##STR1## (wherein R.sup.1 and R.sup.2 are C.sub.1 -C.sub.3 alkyl group or both taken together C.sub.1 -C.sub.3 alkylene group,R.sup.3 is hydrogen atom, dialkylamino group, etc.,R.sup.4 is hydrogen atom, C.sub.1 -C.sub.10 alkyl group,R.sup.5 is C.sub.1 -C.sub.10 alkyl group,m, n, q are an integer from 0-3,p is 0, 1,A ring is ##STR2## B ring is 5 or 6 membered nitrogen containing aromatic ring, are provided, which are useful as medicinals for treating hyperlipemia or atherosclerosis.

Abstract: Pyridine and pyridine N-oxide derivatives of diaryl methyl piperidines or piperazines and pharmaceutically acceptable salts thereof are disclosed, which possess anti-allergic and anti-inflammatory activity. Pharmaceutical compositions containing and methods of using the compounds are also described.

Abstract: An optically active tri-substituted methane compound having, as substituents, an aromatic ring group and a phenyl group having hydroxyl group at ortho or para position can be obtained by allowing a phenol compound unsubstituted at the ortho- or/and para-position to react with an optically active secondary carbinol compound having an aromatic ring group at the alpha-position in the presence of tri-substituted phosphine and diazodicarboxylate or diazodicarboxamide. These and other optically active tri-substituted methane compounds are useful as active ingredients for medicines or as intermediate compounds for preparing medicines.

Abstract: A triphenylmethane derivative represented by the following general formula: ##STR1## exhibits bone absorption inhibiting effects and is useful as a medicament for treating osteoporosis.

Abstract: Compounds which suppress human T-lymphocyte proliferation are disclosed. The active compounds essentially contain at least the following structure: ##STR1## wherein A, R.sup.1, R.sup.2, R.sup.3, n, X.sup.1 and Z are defined in the specification.

Abstract: 4-Phenylpiperidines of the formula ##STR1## wherein R.sub.1 is hydrogen, hydroxy or lower-alkoxy;R.sub.2 is hydrogen, hydroxy, lower-alkanoyl, aroyl, lower-alkoxycarbonyl, lower-alkanoyloxy, lower-alkoxycarbonyl, or CONR.sub.3 R.sub.4 ; R.sub.3 and R.sub.4 are the same or different lower-alkyl or R.sub.3 and R.sub.4 together represent a lower-alkylene chain;X is methylene or carbonyl;Y is methylene, C.dbd.NOH, hydroxymethylene or carbonyl;or pharmaceutically acceptable acid addition salts thereof, are useful in the treatment of psychoses and other ailments of the central nervous system.

Abstract: Methods and compositions are disclosed for enhancing .sup.19 F magnetic resonance imaging which utilize .sup.19 F magnetic resonance contrast media having enhanced .sup.19 F relaxivity. Fluorine-containing compounds having enhanced .sup.19 F relaxation properties resulting from direct association with an unpaired spin are disclosed. The fluorine-containing compound is associated with the unpaired spin by covalent attachment of a stable free radical, by complexation of a fluorinated complexing agent with a paramagnetic metal ion, or by salt formation or charge neutralization of a paramagnetic ion.