The present invention relates to novel ring fused indole-2,3- dione oxime derivatives, a method of treatment therewith, pharmaceutical compositions comprising the compounds and to a method of preparing the novel compounds of the invention.

Object of the Invention

It is an object of the present invention to provide novel isatin derivatives which are useful in the treatment of di¬ seases in mammals, including a human, and especially in the treatment of diseases which can be treated by antagonizing an excitatory amino acid of such mammal.

Another object of the present invention is to provide a method of treating diseases in mammals, including a human, responsive to the blockade of glutamic and aspartic acid receptors which comprises administering to a mammal in need thereof a compound of the invention.

A third object of the present invention is to provide novel pharmaceutical compositions for the treatment of diseases in mammals, including a human, responsive to the blockade of glutamic and aspartic acid receptors.

Background of he Invention

Excessive excitation by neurotransmitters can cause the degeneration and death of neurons. It is believed that this degeneration is in part mediated by the excitotoxic actions

^"

of the excitatory amino acids (EAA) glutamate and aspartate at the N-methyl-D-aspartate (NMDA), the α-amino-3-hydroxy-5- methyl-4-isoxazole propionic acid (AMPA) receptor, and the kainate receptor. This excitotoxic action is responsible for the loss os neurons in cerebrovascular disorders such as cerebral ischemia or cerebral infarction resulting rom a range of conditions, such as thromboembolic or haemorrhagic stroke, cerebral vasospasm, hypoglyσaemia, cardiac arrest, status epilepticus, perinatal asphyxia, anoxia such as from drowning, pulmonary surgery and cerebral trauma as well as lathyrism, Alzheimer's, and Huntington's diseases.

The compounds of the present invention may also be useful in the treatment of schizophrenia, epilepsy, anxiety, pain and drug addiction.

EPA 432648, published June 19, 1991, discloses certain isatinoxime derivatives.

Summary of the Invention

The invention then, inter alia, comprises the following, alone or in combination:

A compound having the formula

wherein

R ⁴ and R ⁵ independently are hydrogen, halogen, CF ₃ , CN, N0 ₂ or

SO _j NR^ ² wherein

R ¹ is hydrogen or C _j . _ε -alkyl which may be straight, branched

or cyclic,

R ² is hydrogen or Ci.g-alkyl which may be straight, branched or cyclic, or wherein R ¹ and R ² together represent -(CH ₂ ) _n -A-(CH ₂ )_-, wherein A is 0, S, CH ₂ or NR ¹ , wherein R ¹ is H, Ci.g-alkyl which may be straight, branched or cyclic, n is 0, 1, 2, 3,

4, 5 and m is 0, 1, 2, 3, 4, 5;

Q is NOH, or 0;

0 O 0

Z = 0, S, N-R ¹² , ^-NR ¹ "*, -NR ^1V -C-NR ^V -, ^s o-C*, wherein R ¹¹ , R ^m , R ^IV and R ^v independently are hydrogen, benzyl, (C=0)CF ₃ , C__ ₆ - acyl, Ci-g-alkoxy which may be branched or cyclic, or C__ ₆ - alkyl which may be straight, branched or cyclic, CH ₂ C0 ₂ R ^VI wherein R ^VI is hydrogen or C^-alkyl which may be straight or branched;

X is -(CH ₂ ) ₀ - wherein o is 0, 1, 2, or 3; Y is -(CH ₂ ) _p - wherein p is 0, 1, 2 or 3; α and β indicate attachment points,

and a compound as above having the formula

wherein R , R ^s and R ¹¹ have the meanings set forth above,

and a compound as above having the formula

wherein R*, R ^s and R ¹¹ have the meanings set forth above.

and a compound as above having the formula

wherein R ⁴ R ⁵ and R ¹¹ have the meanings set forth above,

and a compound as above having the formula

wherein R* and R ⁵ have the meanings set forth above,

and a compound as above having the formula

wherein R* and R ⁵ have the meanings set forth above,

and a method of treating disorders of a mammal, including, a human, responsive to the blockade of glutamic and aspartic acid receptors, which comprises administering to a patient in

need thereof an effective amount of a compound as first above in unit dosage form,

and a method as above wherein cerebrovascular disorders or psychotic disorders are treated,

and further a pharmaceutical composition comprising a thera- peutically-effective amount of a compound as first above together with a pharmaceutically-acceptable carrier,

and a method of preparing a compound having the formula

wherein

R ⁴ and R ⁵ independently are hydrogen, halogen, CF ₃ , CN, N0 ₂ or

S0 ₂ NR ¹ R ² wherein

R ¹ is hydrogen or C _j -g-alkyl which may be straight, branched or cyclic,

R ² is hydrogen or C _x _ ₆ -alkyl which may be straight, branched or cyclic, or wherein R ¹ and R ² together represent -(CH ₂ ) _n -A-(CH ₂ ) _B -, wherein A is 0, S, CH ₂ or NR ¹ , wherein R ¹ is H, C._ ₆ -alkyl which may be straight, branched or cyclic, n is 0, 1, 2, 3,

4, 5 and m is O, 1, 2, 3, 4, 5;

Q is NOH;

0 0 0

Z = 0, S, N-R ¹¹ , ^S C-NR ¹¹¹ *, -NR ^IV -C-NR ^V -, ^S O-C ¹ , wherein R ¹¹ , R ¹¹¹ , R ^IV and R ^v independently are hydrogen, benzyl, acyl, Ci- ₆ -alkoxy which may be branched or cyclic, or C _h ¬ alky1 which may be straight, branched or cyclic, CH ₂ C0 ₂ R ^VI wherein R ^VI is hydrogen or C^-alky! which may be straight or

branched;

X is -(CH ₂ ) ₀ - wherein o is 0, 1, 2, or 3;

Y is -(CH ₂ ) _p - wherein p is 0, 1, 2 or 3; α and β indicate attachment points, which comprise the step reacting a compound as above wherein

Q is oxygen with hydroxylamine or a reactive dereivative thereof.

Biological Activity

The compounds of the invention exhibit valuable biological properties because of their strong excitatory amino acid (EAA) antagonizing properties at the AMPA ((RS)-α-amino-3- hydroxy-5-methyl-4-isoxazolepropionic acid) binding site.

The compound 7-methyl-l,6,7,8-tetrahydrobenzo[2,l-b:3,4-c'] dipyrrole-2,3-dione-3-oxime for example exhibit an IC ₅₀ of 1 μM in the AMPA binding assay as described by T. Honore et al., Neuroscience Letters ____, 27-32 (1985). In the same assay 1,2,3,6,7,8-hexahydro-3-(hydroxyimino)-N,N,7-trim.ethyl-2- oxobenzo[2,l-b:3,4-c']dipyrrole-5-sulfonamide has an IC ₅₀ of 0.3 μM.

The compound 5-nitro-lH,6H-2,3,7,8,9,10-hexahydro-2,3,7- trioxo-azepino[2,3-g]indole-3-oxime in the same test exhibit an IC ₅₀ of 4 μM.

The compound 7-methyl-1,6,7,8-tetrahydrobenzo[2,l-b:3,4-c'] dipyrrole-2,3-dione-3-oxime has an ED ₅₀ of 8 mg/kg when administered i.v. in the AMPA seizure test as described below.

AMPA-induced clonic seizures

AMPA given icv (intracerebroventricular) (15 μg/kg) NMRI to mice induces clonic seizures which should be inhibited by non-NMDA receptor excitatory amino acid antagonists.

_________

Test compound was given i.v. 5 min (or p.o. 30 min) before a 0.3 μg icv administration of AMPA to 10 female NMRI mice (weighing 24-26 g) per dose. The number of mice experiencing clonic seizures within the next 5 min was noted. An ED ₅₀ value was calculated as the dose inhibiting 50% of the mice from having clonic seizures.

Pharmaceutical Compositions

The compounds of the invention, together with a conventional adjuvant, carrier, or diluent, may be placed into the form of pharmaceutical compositions and unit dosages thereof, and in such form may be employed as solids, such as tablets or filled capsules, or liquids such as solutions, suspensions, emulsions, elixirs, or capsules filled with the same, all for oral use, in the form of suppositories for rectal admini¬ stration; or in the form of sterile injectable solutions for parenteral (including subcutaneous) use. Such pharmaceutical compositions and unit dosage forms thereof may comprise conventional ingredients in conventional proportions, with or without additional active compounds or principles, and such unit dosage forms may contain any suitable effective amount of the active ingredient commensurate with the intended daily dosage range to be employed. Tablets containing ten (10) milligrams of active ingredients or, more broadly, 0:1 to one hundred (100) milligrams, per tablet, are accordingly suit¬ able representative unit dosage forms.

Solid forms of pharmaceutical compositions for p.o. admini¬ stration and injectable solutions are preferred.

Method of Treating

The compounds of this invention are extremely useful in the treatment of central nervous system disorders related to

their biological activity. The compounds of this invention may accordingly be administered to a subject, including a human, in need of treatment, alleviation, or elimination of an indication associated with the biological activity of the compounds. This includes especially excitatory amino acid dependent psychosis, excitatory amino acid dependent anoxia, excitatory amino acid dependent ischemia, excitatory amino acid dependent convulsions and excitatory amino acid depen¬ dent migraine. Suitable dosage ranges are 0.1 to 1000 milli¬ grams daily, 10-500 milligrams daily, and especially 30-100 milligrams daily, dependent as usual upon the exact mode of administration, form in which administered, the indication toward which the administration is directed, the subject involved and the body- weight of the subject involved, and further the preference and experience of the physician or veterinarian in charge.

EXAMPLE 1

a) 5-nitro-α-tetralpne

10 ml (75 mmol) of α-tetralone was added dropwise to 7.6 g (75 mmol) of potassium nitrate dissolved in 75 ml of concentrated sulfuric acid (at -10°C). The resulting mixture was poured onto ice and the precipitate was sus¬ pended in ether. The precipitate (the 7 nitro isomer) was filtered off and the ether solution was evaporated. The residue was purified by column chromatography on silica gel. Yield: 4.7 g of the title compound, M.p. 94- 96°C.

b) 6-nitro-2-oxo-l-benzazep_ne

The product of example la) above, 2.43 g (35 mmol) of hydroxylamine hydrochloride and 3.7 g (35 mmόl) of disodium carbonate was added to 100 ml of methanol and the mixture was refluxed for 90 minutes, whereafter it was cooled and neutralized with aqueous acetic acid. The resulting precipitated oxime was isolated (4.3 g), M.p. 139-141 ^C C. This product was heated with stirring at 110°C in polyphosphoric acid (50 g) for 30 minutes. The reaction mixture was poured onto crushed ice. This afforded a solid precipitate of the title product which was isolated by filtration and purified by wash with water and ether, M.p. 150-155 ^C C.

c) 6-amino-2-oxo-l-benzazepine

The product of example lb) was hydrogenated under stan¬ dard procedures at 1 atm catalyzed by Pd/C in ethanol. Yield of title compound 2.0 g, M.p. 175-178°C.

d) 1H.6H-2.3.7.8.9.lO-hexahydro-2.3.7- rioxo-azeninor2.3- gl indole

The product of example lc) and 2 ml (13 minol) of diethyl ketomalonate in 20 ml of glacial acetic acid was refluxed for our hours, whereaf er the mixture was cooled and concentrated by evaporation, the residue was heated (~60-80°C) in 25 ml 5% of NaOH while exposed to air for 2 hours. The mixture was then cooled and concen¬ trated hydrochloric acid was added to pH — 0. The formed precipitate was isolated by filtration. Yield: 0.55 g, M.p. >300 ^β C.

e) 1H.6H-2,3 , 7 ,8,9,10-he -hydro-2,3,7--.riQXO-azep_.np \2,3- g-1indole-3-oxime

0.23 g of the product of example Id), 0.1 g (1.3 mmol) of hydroxyl amine hydrochloride and 0.14 g (1.3 mmol) of disodium carbonate was stirred in 10 ml of methanol for 6 hours, wherea ter water was added (20 ml). The precip¬ itated product was filtered off. Yield of the title com¬ pound 0.2 g, M.p. 256-258°C.

In a similar manner the following oximes were prepared from the corresponding keto analogs

6,7,9,10-tetrahydro-5-nitro-pyrrolo[2,3-g] [2,4]benzodia- zepine-2,3,8(lH)trione-3-oxime, M.p. >300 ^β C.

6,7,9,10-tetrahydropyrrolo[2,3-g][2,4]benzodiazepine- 2,3,8(lH)trione-3-oxime, M.p. >300°C.

6,8-dihydro-lH-thieno[3,4-g]indole-2,3-dione-3-oxime, M.p. 192-195 ^β C.

6,8-dihydro-lH-furo[3,4-g]indole-2,3-dione-3-oxime, M.p. >300°C.

8-acetyl-l,6,7,8-tetrahydrobenzo[2,1-b:3,4-b']dipyrrole- 2,3-dione-3-oxime, M.p. 244-245°C.

EXAMPLE 2

a) 5-ni-ro-lH-βH-2.3.7 _r 8.9.10-hexahydro-2.3.7-trioxo- azepinor∑.3-ςrlindolg

0.25 g of the product of example la) was added to 0.12 g (1.2 mmol) of potassium nitrate in concentrated sulphuric acid (10 ml) at -5 ^C C after 10 min stirring the reaction mixture was poured onto crushed ice. The re¬ sulting mixture was extracted with ethyl acetate, and the organic solvent was allowed to evaporate. This left the title compound as yellow crystals. Yield: 0.1 g, M.p. 277-278°C.

In the same manner was prepared by nitration 6,7,9,10- tetrahydro-6-nitro-pyrrolo[2,3-g] [2,4]benzodiazepine- 2,3,8(lH)trione, M.p. >300 ^β C.

b) 5-nitro-lH.6H-2.3.7.8.9.lO-hexahydro-2.3.7-trioxo- azepinor∑.3-σlindole-3-oxime

A mixture of the product of example 2a) and 35 mg (0.5 mmol) of hydroxylamine hydrochloride and 53 mg (0.5 mmol) disodium carbonate in 6 ml of methanol was stirred for 2 hours, whereafter water and acetic acid was added to neutral reaction. The precipitate was isolated by filtration. Yield of the title compound 0.1 g, M.p. 232- 234°C.

EXAMPLE 3

a) 2.3-difbromome_hγl -nitrobenzene

30 g of N-bromo-succinimide (NBS) was added portionwise to 9 g of 2,3-dimethyl-nitrobenzene, and 0.25 ml of t- butyl perbenzoate in 100 ml of carbontetrachloride and the mixture was refluxed for 24 hours. The reaction

mixture was thereafter cooled and ether was added. The succinimide was filtered off, and the filtrate was evaporated to give the title compound (18 g) as an oil which could be crystallized from ethanol, M.p. 68-70°C.

N-methyl-4-ni ro-2H-l.3-dihydro-Dvrrolor3.41benzene

20 g of the product of example 3a) was dissolved in 300 ml of methylene chloride at 10 ^β C. Methylamine was led through the solution until TLC shows only small amounts of the starting material left in the solution. The reaction mixture was extracted with water and thereafter with 4N hydrochloric acid (150 ml). pH of the aqueous phase was adjusted to 10 with 4N NaOH. This treatment left the title compound as pale crystals which was isolated by filtration. Yield of the title compound as the hydrochloride 2.5 g, M.p. >300 ^β C.

In a similar manner the following compounds were pre¬ pared

N-t-butyl-4-nitro-2H-l,3-dihydro-pyrrolo[3,4]benzene, M.p. 233-235°C (hydrochloride) from reaction with t- butyl amine.

N-ethyl-4-nitro-2H-l,3-dihydro-pyrrolo[3,4]benzene, M.p. 250°C (decomposes) from reaction with ethylamine.

N-benzyl-4-nitro-2H-l,3-dihydro-pyrrolo[3,4]benzene, M.p. 238-239°C (hydrochloride) from reaction with benzylamine.

N-me_hoxy-4-nitro-2H-l,3-dihydro-pyrrolo[3,4]benzene hydrochloride from reaction with O-methylhydroxyl-amine hydrochloride oil.

C) 1.2.4.5-tetrahydro-5-nitro-3-oxor2.41benzodiazepine.

2,3-di-aminomethyl-nitrobenzene, M.p. 93-95 ^c C.

A mixture of potassium phthalimid (11 mmol) and 2,3- dibromomethyl-nitrobenzene (5 mmol) was stirred at reflux temperature in THF (30 ml) and DMF (10 ml) for 2 hours.

The formed precipitate was filtered off and treated with hydrazine hydrate (0.75 ml) in methanol (50 ml). This mixture was refluxed for 3 hours, cooled to room temper¬ ature and filtered. The filtrate was evaporated, and the residue was stirred in CH ₂ C1 ₂ . The filtrated CH ₂ C1 ₂ solu¬ tion was then evaporated to give the title compound as light pink crystals, M.p. 93-95°C.

10 mmol of the product described above was dissolved in dry DMF (50 ml). N,N-carbonyldiimidazole (15 mmol) was added, whereafter the solution was refluxed for 2 hours. After cooling, the precipitated product was filtered off as white crystals, M.p. 260-265°C (decomp.).

d) 2-methγl-4-amino-2H-l _r 3-dihydro-pγrrolor3.41benzene hydrochloride

4.2 g of the product of example 3b was hydrogenated under standard procedure with Pd/C as catalyst in etha- nol. Yield: 3.2 g of the title compound, M.p. 147-150°C.

The following amines were likewise obtained by hydroge- nation from the corresponding nitro analogs.

2-t-butyl-4-amino-2H-l,3-dihydro-pyrrolo[3,4]benzene hydrochloride oil.

2-benzyl-4-amino-2H-l,3-dihydro-pyrrolo[3,4]benzene

hydrochloride oil.

2-methoxy-4-amino-2H-l,3-dihydro-pyrrolo[3,4]benzene hydrochloride oil.

l-acetyl-7-amino indoline, M.p. 156-158 ^β C from hydroge- nation of l-acetyl-5-bromo-7-nitro indoline.

3-amino-benzo[3,4]butyro lactone hydrochloride, M.p. 227-230°C.

4-amino-l,3-dihydro benzo[c]furan hydrochloride, M.p. 238-241°C.

1,2,4,5-tetrahydro-5-amino-3-oxo-2,4-benzodiazepine, M.p. 222-224°C.

4-amino-l,3-dihydro benzo[c]thiophene oil. Raney Ni was used as catalysist.

5-amino-2-methyl-l,2,3,4-tetrahydro isoquinoline. Oil from hydrogenation of 2-methyl-5-nitro isoquinolinium methyl sulphate with Pto ₂ at catalysist.

e) 7-methyl-l.6.7.8- etrahydrnhp.nzo \2.1-b:3. -c'1dipvrrole-

2,3-djpne

2.2 g of the product of example 3d), 3.0 g of hydroxyl- amine hydrochloride, 1.93 ml of chlorale in 70 ml water and 16 g of disodium sulphate was heated to 100 ^β C for 30 min. The solution was cooled and pH adjusted to 8 with Na ₂ C0 ₃ . This afforded a crystalline precipitate which was filtered off and washed with water. After drying, the crystals were dissolved in 20 ml of concentrated sulphuric acid and heated with stirring to 100°C for 15- 20 minutes. The mixture was cooled and crushed ice 100 g was added followed by 15 ml of 30% sodium hydroxide.

Thereafter saturated aqueous disodium carbonate was added until pH was 9. The formed precipitate was isolat¬ ed, and was thereafter recrystallized from ethanol. Yield of the title compound 1.6 g, M.p. 163-165°C.

In a similar manner were prepared 7-(l,l-dimethylethyl)- l,6,7,8-tetrahydrobenzo[2,l-b:3,4-c']dipyrrole-2,3- dione, M.p. 178-180 ^β C.

7-ethyl-l,6,7,8-tetrahydrobenzo[2,1-b:3,4-c' ]dipyrrole- 2,3-dione, M.p. 168-170°C.

1,6,7,8-tetrahydro-7-methoxybenzo[2,1-b:3,4-c']- dipyrrole-2,3-dione, M.p. 174-176°C.

l,6,7,8-tetrahydro-7-(phenylmethyl)benzo[2,l-b: :3,4-c']- dipyrrole-2,3-dione, M.p. >300°C.

6,8-dihydro-lH-thieno[3,4-g]indole-2,3-dione, M.p. >300 ^β C.

6,8-dihydro-lH-furo[3,4-g]indole-2,3-dione, M.p. >300°C.

8-acetyl-l,6,7,8-tetrahydrobenzo[2,1-b:3,4-b' ]dipyrrole- 2,3-dione, M.p. >300°C.

6,7,9,10-tetrahydropyrrolo[2,3-g][2,4]benzodiazepine- 2,3,8(lH)-trione, M.p. >300°C.

lH-furo[3,4-g]indole-2,3,6(8H)-trione, M.p. >300 ^β C.

6,7,8,9-tetrahydro-7-methyl-lH-pyrrolo[2,3-f]isoquino- line-2,3-dione, M.p. >300°C.

6,7,8,9-tetrahydro-7-ethoxycarbonylmethyl-lH-pyrrolo- [2,3-f]isoquinoline-2,3-dione, M.p. 180-183 ^β C.

6, 7, 8, 9-tetrahydro-7-trif luoroacetyl-lH-pyrrolo[2, 3- f] isoquinoline-2, 3-dione, M.p. 216-219 °C.

6, 7,8, 9-tetrahydro-7-acetyl-lH-pyrrolo [2 , 3-f ] isoquino- line-2,3-dione, M.p. 248-250°C.

EXAMPLE 4

7-acetyl-6,7,8,9-tetrahydro-5-nitro-IH-pyrrolo[2,3- f]isoquinoline-2,3-dione, M.p. >300°C was obtained from nitration of 7-acetyl-6,7,8,9-tetrahydro-IH-pyrrolo[2,3- f]isoquinoline-2,3-dione in 98% sulphuric acid and KN0 ₃ .

EXAMPLE 5

5-bromo-l,6,7,8-tetrahydro-7-methylbenzo[2,1-b:3, - c']dipyrrole-2,3-dione.

To a stirred suspension of l,6,7,8-tetrahydro-7-methyl- benzo[2,l-b:3,4-c']dipyrrole-2,3-dione (0.5 g, 2.48 mmol) in water (20 ml) was added a solution of bromine (0.7 ml) in ethanol (5 ml). After 5 hours stirring at room temperature the reaction was completed and pH was adjusted to 8 with sat Na ₂ C0 ₃ . The precipitated product was filtered off and washed with water, M.p. >300°C.

Substitution of bromine with chlorine gave likewise 5- chloro-1,6,7,8-tetrahydro-7-methylbenzo[2,l-b:3,4-c']- dipyrrolo-2,3-dione, M.p. >300 ^β C.

EXAMPLE 6

6,7,8,9-tetrahydro-lH-pyrrolo[2,3-f]isoquinoline-2,3- dione.

To an ice cooled stirred suspension of 6,7,8,9-tetra- hydro-7-methyl-IH-pyrrolo[2,3-f]isoquinoline-2,3-dione

(500 mg) in 1,2-dichloroethane (10 ml) was added α- chloroethylchloroformate (0.25 ml). The mixture was then brought to reflux for 1 hour, whereafter it was cooled to room temperature and filtered. The filtrate was evaporated, the residue dissolved in methanol (10 ml) and refluxed for 10 min. Evaporation of the solvent left the crude title compound as a solid, M.p. 270°C.

EXAMPLE 7

7-(1.1-dime hylethγlϊ-1.2.3.6.7.8-he ahydro-3-(hydroxy- imino )-N.N-dimethyl-2-oxobenzoT2.1-b:3.4-c'1dipyrrole-5- sulphonamide.

1,6,7,8-tetrahydro-7-(dimethylethyl)benzo[2,1-b:3,4-c*]- dipyrrole-2,3-dione (0.5 g) was dissolved in chloro- sulphonic acid (2 ml). The solution was heated to 80 ^β C for 10-20 min, then cooled and the excess of chloro- sulphonic acid was destroyed by addition of neat NaCl, followed by addition of 2 ml water. After some time a precipitate of 7-(dimethylethyl)-1,2,3,6,7,8-hexahydro- 3,3-dichloro-2-oxobenzo[2,1-b:3,4-c']dipyrrole-5- sulphonylchloride, hydrochloride was formed. The precipitate was filtered off, washed with 4N HC1 and dried. Thereafter it was brought into solution in dry THF (20 ml), undissolved inorganic material was removed by filtration. To the THF solution was added dimethyl- amine until complete reaction (followed by TLC). The reaction mixture was filtered and the solvent was re¬ moved by evaporation. This left the crude 7-(l,l- dimethylethyl)-l,2,3,6,7,8-hexahydro-3,3-dichloro-N,N- dimethyl-2-oxobenzo[2,l-b:3,4-c']dipyrrole-5-sulphon- a ide as a oily residue which was reacted with hydroxyl- amine, hydrochloride (100 mg) in refluxing methanol (5 ml).

After 1 hour reflux the reaction mixture was cooled to

ambient temperature and the product (title compound) was filtered off as the monohydrochloride, M.p. (free base) 242-244 ^β C.

In a similar manner was prepared 7-ethyl-l,2,3,6,7,8- hexahydro-3-(hydroxyimino)-N,N-dimethyl-2-oxobenzo[2,1- b:3, -c']dipyrrole-5-sulphonamide monohydrochloride, M.p. >300 ^β C.

1,2,3,6,7,8-hexahydro-3-(hydroxyimino)-N,N,7-trimethyl- 2-oxobenzo[2,l-b:3,4-c']dipyrrole-5-sulfonamide, M.p. >300 ^β C.

1,2,3,6,7,8-hexahydro-3-(hydroxyimino)-N,N,7-trimethyl- 2-oxobenzo[2,1-b:3,4-c']dipyrrole-5-sulfonamide mono¬ hydrochloride, M.p. >300°C.

1,2,3,6,7,8-hexahydro-3-(hydroxyimino)-N,7-dimethyl-2- oxobenzo[2,1-b:3,4-c*]dipyrrole-5-sulfonamide monohydro¬ chloride, M.p. >300 ^β C.

1-[[1,2,3,6,7,8-hexahydro-3-(hydroxyimino)-7-methyl-2- oxobenzo[2,l-b:3,4-c ^f ]dipyrrole-5-yl]sulfonyl]pyrro- lidine monohydrochloride, M.p. >300 ^β C.

1,2,3,6,7,8-hexahydro-3-(hydroxyimino)-7-methyl-2- oxobenzo[2,l-b:3,4-c']dipyrrole-5-sulfonamide monohydro¬ chloride, M.p. >300 ^β C.

2,3,6,7,8,9-hexahydro-3-(hydroxyimino)-N,N,7-trimethyl- 2-oxo-IH-pyrrolo[2,3-f]isoquinoline-5-sulfonamide mono¬ hydrochloride., M.p. 268 ^β C.

7-acetyl-5-(N,N-dimethylsulphamoyl)-6,7,8,9-tetrahydro- lH-pyrrolo[2,3-f]isoquinoline-2,3-dione-3-oxime, M.p. 260-261 ^β C.

EXAMPLE 8

7-mathγl-l.6.7.8-tetrahydrobenzor2.1-b:3.4-c'Idipyrrole- 2.3-d_one-3-oxime

200 mg of the product of example 3e), 150 mg of disodium carbonate and 100 mg of hydroxylamine hydrochloride in 20 ml methanol was stirred for 3 hours at reflux temper¬ ature. Then water and acetic acid was added to the reac¬ tion mixture and sodium hydrogen carbonate was thereaf¬ ter added until pH - 8. The crystalline precipitate was isolated by filtration. Yield of the title compound 200 mg, M.p. >300°C.

In a similar manner were prepared 7-(l,l-dimethylethyl)- l,6,7,8-tetrahydrobenzo[2,l-b:3,4-c']dipyrrole-2,3- dione-3-oxime, M.p. 242-244 ^β C.

7-ethyl-1,6,7,8-tetrahydrobenzo[2,1-b:3,4-c']dipyrrole- 2,3-dione-3-oxime, hydrochloride, M.p. >300°C.

1,6,7,8-tetrahydro-7-methoxybenzo[2,1-b:3,4-c']- dipyrrole-2,3-dione-3-oxime, M.p. >300 ^β C.

1,6,7,8-tetrahydro-7-(phenylmethyl)benzo[2,1-b:3,4-c']- dipyrrole-2,3-dione-3-oxime, M.p. >300°C.

6,7,8,9-tetrahydro-7-methyl-lH-pyrrolo[2,3-f]isoquino- line-2,3-dione-3-oxime, M.p. 193-195°C.

6,7,8,9-tetrahydro-IH-pyrrolo[2,3-f]isoquinoline-2,3- dione-3-oxime, hydrochloride, M.p. >300°C.

7-acetyl-6,7,8,9-tetrahydro-lH-pyrrolo[2,3-f]isoquino- line-2,3-dione-3-oxime, M.p. 190-193°C.

7-acetyl-5-nitro-6,7,8,9-tetrahydro-lH-pyrrolo[2,3-

f]isoquinoline-2,3-dione-3-oxime, M.p. 217-219°C.

6,7,8,9-tetrahydro-7-tri luoroacetyl-lH-pyrrolo[2,3- f]isoquinoline-2,3-dione-3-oxime, M.p. 251-253°C.

7-ethoxycarbonylmethyl-6,7,8,9-tetrahydro-lH-pyrrolo- [2,3-f]isoquinoline-2,3-dione-3-oxime, M.p. 212-214 ^C C.