The present invention relates as new industrial product to a derivative of pyrano-indole chosen from the group constituted by: PA0 (i) the pyrano[2,3-g]indoles of general formula: ##STR1## in which: X represents a group ##STR2## (where R is a lower alkyl group, OH, lower alkoxy, tosyloxy, NH.sub.2) or >CH--NR'R" (where R' and R", which are identical or different, each represent H or a lower alkyl); PA0 R.sub.1 represents an atom of hydrogen, a lower alkyl group, or COY.sub.1 (where Y.sub.1 is a lower alkyl group, an amino acid group CH.sub.2 CH(COOH) NH.sub.2 or an aminoalkylene group --(CH.sub.2).sub.n --NR'R" in which n is a whole number between 1 and 4 and R' and R" are defined as hereinabove); PA0 R.sub.2 represents an atom of hydrogen, or a COY.sub.2 group (where Y.sub.2 is OH or lower alkoxy; PA0 R.sub.3 represents an atom of hydrogen, an atom of halogen, a CHO group, lower alkyl, CF.sub.3, (CH.sub.2).sub.n NR'R" or CO--CONR'R" (where n, R' and R" are defined as hereinabove, and PA0 R.sub.4 represents an atom of hydrogen, an atom of halogen, an OH group, lower alkyl, lower alkoxy, CF.sub.3 or NR'R" (where R' and R" are defined as hereinabove); PA0 (ii) the pyrano[3,2-f]indoles of general formula: ##STR3## where X, R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are defined as hereinabove; and PA0 (iii) their acid addition salts. The invention also relates to the process for preparing this derivative and to its application in therapeutics.

The present invention relates as new industrial product to a pyrano-indole 
derivative. It also relates to the process for preparation thereof and to 
its application in therapeutics, particularly as anti-ulcerous, 
anti-inflammatory and antalgic agent. 
The derivative according to the invention is chosen from the group 
constituted by: 
(i) the pyrano[2,3-g]indoles of general formula: 
##STR4## 
in which 
X represents a group 
##STR5## 
(where R is a lower alkyl group, OH, lower alkoxy, tosyloxy, NH.sub.2) or 
&gt;CH--NR'R" (where R' and R", which are identical or different, each 
represent H or a lower alkyl); 
R.sub.1 represents an atom of hydrogen, a lower alkyl group, or COY.sub.1 
(where Y.sub.1 is a lower alkyl group, an amino acid group CH.sub.2 
CH(COOH) NH.sub.2 or an aminoalkylene group --(CH.sub.2).sub.n --NR'R" in 
which n is a whole number between 1 and 4 and R' and R" are defined as 
hereinabove); 
R.sub.2 represents an atom of hydrogen, or a COY.sub.2 group (where Y.sub.2 
is OH or lower alkoxy; 
R.sub.3 represents an atom of hydrogen, an atom of halogen, a CHO group, 
lower alkyl, CF.sub.3, (CH.sub.2).sub.n NR'R" or CO--CONR'R" (where n, R' 
and R" are defined as hereinabove) and 
R.sub.4 represents an atom of hydrogen, an atom of halogen, an OH group, 
lower alkyl, lower alkoxy, CF.sub.3 or NR'R" (where R' and R" are defined 
as hereinabove); 
(ii) the pyrano[3,2-f]indoles of general formula: 
##STR6## 
where X, R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are defined as hereinabove; 
and 
(iii) their acid addition salts. 
Lower alkyl group is understood here to mean a hydrocarbon radical with 
straight or branched chain and with 1-4 carbon atoms. Lower alkoxy group 
is understood to mean a straight or branched chain group with 1-4 carbon 
atoms. From suitable lower alkyl and lower alkoxy groups, particular 
mention may be made of CH.sub.3, CH.sub.2 CH.sub.3, CH.sub.2 CH.sub.2 
CH.sub.3, CH(CH.sub.3).sub.2, C(CH.sub.3).sub.3, OCH.sub.3, OCH.sub.2 
CH.sub.3, OCH(CH.sub.3).sub.2 and OC(CH.sub.3).sub.3. 
Atom of halogen is understood here to mean an atom of fluorine, chlorine, 
bromine or iodine, the preferred atoms of halogen being bromine and 
chlorine. 
A certain number of pyrano-indole derivatives according to the invention 
have been given, in non-limiting manner, in Tables I and II hereinbelow. 
The process for preparing a pyrano-indole compound according to the 
invention is illustrated by the reactional mechanisms of diagram 1 
hereinbelow. This process is characterised in that: 
(a) a pyrano-indole-carboxylate of formula IX is prepared as follows: 
(i) the aldehyde of formula VII (where X and R.sub.4 are defined as 
hereinabove) is reacted with ethyl azidoacetate in the presence of a lower 
alcohol (particularly C.sub.2 H.sub.5 OH and preferably CH.sub.3 OH) and 
of an alkali metal (particularly Na and K) at a temperature of -5.degree. 
C. to +5.degree. C. (preferably 0.degree. C.) for at least 3 hours, to 
obtain an azide of formula VIII, and 
(ii) said azide VIII is cyclized in the presence of an inert solvent 
(preferably an aromatic solvent such as benzene, toluene, xylene) at the 
reflux temperature of the reaction medium for at least 1 hour, to obtain 
said pyrano-indole-carboxylate IX (which is a derivative of formula 
I.sub.o where R.sub.1 =R.sub.3 =H and R.sub.2 which represents a 
carboxylate radical is preferably COOCH.sub.3), then 
(b) if necessary, said pyrano-indole-carboxylate is converted into 
corresponding acid, esters and amides by saponification, 
transesterification and transamidification, respectively. 
The best mode of preparing all the compounds of formulae I.sub.o and 
I'.sub.o (which is also illustrated in diagram 1 hereinbelow) consists in 
(c) saponifying the ester IX to obtain the corresponding acid X (which is a 
derivative of formula I.sub.o where R.sub.1 =R.sub.3 =H and R.sub.2 
=COOH), 
(d) decarboxylating said axid X by means of a catalyst, preferably copper 
chromite prepared from CuO and Cr.sub.2 O.sub.3) in the presence of inert 
solvent (preferably quinoline at 180.degree.-200.degree. C. under 1 
atmosphere) to obtain (i) a mixture of compounds XI and XI' when R.sub.4 
=H which is separated in particular by chromatography on silica and (ii) 
compound XI only when R.sub.4 is different from H, then 
(e) if necessary, introducing at least one of the groups R.sub.1 and 
R.sub.3, different from H, to obtain, from XI and XI' respectively the 
compounds XII and XII'; and, if need be, introducing the group R.sub.4 
different from H to obtain the compound XII' from compound XI'. 
The acid R.sub.2 =COOH group may of course be esterified, amidified and 
decarboxylated. 
The compounds VII, which intervene as raw materials in the process of 
synthesis of the pyrano-indoles of formulae I.sub.o and I'.sub.o, may be 
prepared according to a method known per se, by application of 
conventional reactional mechanisms. 
According to the invention, several routes are recommended for synthesis 
thereof, as a function of the nature of group X. These routes are 
illustrated by diagrams 2 and 3 hereinbelow. 
Route A shown in diagram 2 envisages obtaining a particular derivative VII 
when the group X is CH.sub.2. In a first variant, (when X is CH.sub.2 and 
R.sub.4 is H), the 6-bromo-chroman of formula Ia is subjected to a 
reaction with CuCN in the presence of dimethylamine (DMA) to yield the 
corresponding 6-cyano-chroman, which is then subjected to a reaction of 
reduction, particularly in the presence of Ni and of NaH.sub.2 PO.sub.2 to 
yield the 6-chromanylcarbaldehyde derivative of formula IIa. In a second 
variant (when X is CH.sub.2 and R.sub.4 is different from H), a 
6-bromo-chroman substituted in 8 position, of formula Ib is subjected to a 
reaction with an organolithian (preferably butyllithium) within the 
dimethylformamide, to obtain a 5-chromanyl carbaldehyde substituted in 8 
position, of formula IIb. 
Route B, shown in diagram 3, envisages obtaining a particular derivative 
VII (in which X is 
##STR7## 
R.sub.4 being any). This route consists in reacting a 5-bromo-chromanone 
of formula III by means of HOCH.sub.2 CH.sub.2 OH or HOCH.sub.2 CH.sub.2 
CH.sub.2 OH in an inert solvent (preferably an aromatic solvent such as 
benzene, toluene and xylene) in the presence of p-toluene-sulfonic acid 
(ATPS), to obtain a brominated derivative of IV where X is 
##STR8## 
in subjecting the product IV thus obtained to a reaction with an 
organolithian (preferably butyllithium) within the dimethylformamide to 
replace the bromo group in CHO group and obtain a derivative of formula V 
where X is 
##STR9## 
this acetal derivative being, if necessary, converted into 6-formyl 
chromanone derivative of formula VI by acid hydrolysis. 
The intermediate compounds IIb, IV, V and VI, which intervene in the 
synthesis of the pyrano-indole derivatives of the invention, are novel. 
Further advantages and features of the invention will be more readily 
understood on reading the following examples of preparation given by way 
of non-limiting illustration. "Preparations I-XI" relative to obtaining 
the raw materials will be found hereinafter, then Examples 1-31 given in 
Tables I and II hereinbelow. 
Preparation I 
6-bromo-8-chloro-chroman (I b.sub.1) 
To the amalgam of zinc--prepared from 1280 g (19.7 gram-atoms) of zinc, 128 
g (5.4.times.10.sup.-1 M) of mercurous chloride, 64 cm.sup.3 of 
concentrated hydrochloric acid and 1900 cm.sup.3 of water--are added, in 
order, 1000 cm.sup.3 water, 1500 cm.sup.3 of concentrated hydrochloric 
acid, 3500 cm.sup.3 of toluene and 640 g (2.45 M) of 
6-bromo-8-chloro-4-chromanone (III.sub.2). The mixture is refluxed for 1 
hour and, after cooling and decantation, it is extracted with ether and 
washed in water up to neutrality. 305 g (yield=50%) of expected product 
are thus isolated. B.p..sub.0.01 =128.degree. C. 
Analysis: C.sub.9 H.sub.8 OBrCl: % calculated: C: 43.68, H: 3.23, Br: 
32.29, % found: C: 43.5, H: 3.2, Br: 32.0. 
Preparation II 
6-bromo-8-methoxy-chroman (I b.sub.2) 
According to the process of preparation I, from the amalgam of zinc 
prepared from 915 g (14 gram-atoms) of zinc, 91 g (3.8.times.10.sup.-1 M) 
of mercurous chloride in 46 cm.sup.3 of concentrated hydrochloric acid and 
1350 cm.sup.3 of water, after addition of 700 cm.sup.3 of water, 1100 
cm.sup.3 of concentrated hydrochloric acid, 2500 cm.sup.3 of toluene and 
450 g (1.8 M) of 6-bromo-8-methoxy-4-chromanon (III.sub.1), 200 g 
(yield=47%) of the expected product are obtained. M.p.=67.degree. C. 
Analysis: C.sub.10 H.sub.11 O.sub.2 Br: % calculated: C: 49.42, H: 4.52, O: 
13.16, Br: 32.88, % found: C: 49.4, H: 4.5, O: 13.5, Br: 32.6. 
Preparation III 
8-chloro-chroman-6-carbaldehyde (II b.sub.1) 
72 g (2.9.times.10.sup.-1 M) of dihalochroman Ib.sub.1 dissolved in 250 
cm.sup.3 of anhydrous ether are added slowly and with stirring in 
2.9.times.10.sup.-1 M of n-butyllithium in 320 cm.sup.3 of anhydrous 
ether. The temperature is maintained at -70.degree. C. for 6 hours then 31 
g (3.8.times.10.sup.-1 M) of N,N-dimethylformamide dissolved in 150 
cm.sup.3 of anhydrous ether are added drop by drop. The reaction mixture 
is further maintained at the same temperature for 12 hours, with stirring, 
then--after return to ambient temperature--it is poured on glacial water. 
After acidification with 5 N hydrochloric acid, extraction with ether and 
evaporation, 54 g (yield=95%) of 8-chloro-chroman-6-carbaldehyde are 
isolated, m.p.=51.degree. C. 
Analysis: C.sub.10 H.sub.9 O.sub.2 Cl: % calculated: C: 61.11, H: 4.57, O: 
16.27, Cl 18.03, % found: C: 61.2, H: 4.6, O: 16.3, Cl: 18.0. 
Preparation IV 
8-methoxy-chroman-6-carbaldehyde (II b.sub.2) 
The procedure is as according to the method described for preparation III, 
but maintaining the temperature at -50.degree. C. From 186 g 
(7.7.times.10.sup.-1 M) of bromo-methoxy-chroman Ib.sub.2 in 500 cm.sup.3 
of anhydrous ether and 7.7.times.10.sup.-1 M of n-butyllithium in 650 
cm.sup.3 of anhydrous ether, and after addition of 78 g (1.1 M) of 
N,N-dimethylformamide in 200 cm.sup.3 of anhydrous ether and 
recrystallisation in isopropyl ether, 75 g (yield=51%) of expected 
compound are isolated. m.p.=81.degree. C. 
Analysis: C.sub.11 H.sub.12 O.sub.3 : % calculated: C: 68.77, H: 6.24, O: 
24.97, % found: C: 69.0, H: 6.3, O: 25.2. 
Preparation V 
B 6-bromo-8-methoxy-4-chromanon (III.sub.1) 
34 g (3.5.times.10.sup.-1 M) of phosphoric acid are added--at 0.degree. 
C.--in a mixture containing 475 cm.sup.3 of anhydrous benzene and 56 g 
(4.times.10.sup.-1 M) of phosphoric anhydride. After having boiled for 4 
hours, 83 g (3.times.10.sup.-1 M) of 
3(4-bromo-2-methoxy-1-phenoxy)-propionic acid are slowly added. The 
mixture is maintained at boiling point for 12 hours, then, after cooling, 
poured onto glacial water, treated with 5 N hydrochloric acid and 
extracted with ether. After usual treatment and recrystallisation of the 
solid obtained in ethanol, 67 g (yield=86%) of expected compound are 
isolated. m.p. 137.degree. C. 
Analysis: C.sub.10 H.sub.9 O.sub.3 Br: % calculated: C: 46.73, H: 3.50, O: 
18.66, Br: 31.09, % found: C: 46.7, H: 3.5, O: 18.7, Br: 31.3. 
Preparation VI 
6-bromo-8-chloro-4-chromanon (III.sub.2) 
A mixture of 279 g (1 M) of 3-(4-bromo-2-chloro-1-phenoxy)-propionic acid 
and 127 g (1.3 M) of concentrated sulfuric acid is taken for 2 hours to 
70.degree.-80.degree. C. The reaction mixture is then poured onto glacial 
water, extracted with ether, washed with a dilute solution of ammonia then 
with water. 183 g (yield=70%) of expected product is finally obtained. 
m.p.=109.degree. C. 
Analysis: C.sub.9 H.sub.6 O.sub.2 BrCl: % calculated: C: 41.34, H: 2.29, O: 
12.23, % found: C: 41.3, H: 2.4, O: 12.1. 
Preparation VII 
Dioxolan of 6-bromo-8-methoxy-4-chromanon (IV.sub.1) 
10 g (3.9.times.10.sup.-2 M) of 4-chromanon III.sub.1, 24 g 
(3.9.times.10.sup.-1 M) of ethylene glycol and 0.3 g (1.7.times.10.sup.-3 
M) of paratoluene sulfonic acid in 200 cm.sup.3 of anhydrous toluene are 
taken to boiling point for 7 hours in a Dean and Stark apparatus. The 
reaction mixture is then poured onto glacial water, extracted with ether 
and the solid obtained is recrystallised in an ethyl alcohol-ether 
mixture. 9.6 g (yield=82%) of expected product are obtained. 
m.p.=104.degree. C. 
Analysis: C.sub.12 H.sub.13 O.sub.4 Br: % calculated: C: 47.88, H: 4.31, O: 
21.25, Br: 26.54, % found: C: 47.8, H: 4.5, O: 21.3, Br: 26.4. 
Preparation VIII 
Dioxolan of 6-bromo-8-chloro-4-chromanon (IV.sub.2) 
Similarly, 30 g (1.1.times.10.sup.-1 M) of 4-chromanon (III.sub.2), 71 g 
(1.1 M) of ethylene glycol and 0.2 g (1.1.times.10.sup.-3 M) of 
paratoluene sulfonic acid in 200 cm.sup.3 of toluene, lead, after 
recrystallation in a benzene-isopropyl ether mixture, to 34 g (yield=97%) 
of expected product. m.p.=94.degree. C. 
Analysis: C.sub.11 H.sub.10 O.sub.3 BrCl: % calculated: C: 43.25, H: 3.27, 
O: 15.70, % found: C: 43.2, H: 3.2, O: 15.6. 
Preparation IX 
4-dioxolano-8-methoxy-chroman-6-carbaldehyde (V.sub.1) 
177 g (5.9.times.10.sup.-1 M) of dioxolan IV.sub.1 dissolved in 500 
cm.sup.3 of anhydrous ether are added slowly at -70.degree. C. to 
5.9.times.10.sup.-1 M of n-butyllithium in 570 cm.sup.3 of anhydrous 
ether. After addition, the medium is maintained for 6 hours at -70.degree. 
C. and 56 g (7.7.times.10.sup.-1 M) of N,N-dimethylformamide dissolved in 
300 cm.sup.3 of anhydrous ether are added drop by drop. The reaction 
mixture is maintained for 12 hours at -70.degree. C. then, after return to 
ambient temperature, poured onto glacial water. After extraction with 
chloroform, recrystallisation of the solid obtained in ethanol, 133 g 
(yield=90%) of expected product are isolated. m.p.=167.degree. C. 
Analysis: C.sub.13 H.sub.14 O.sub.5 : % calculated: C: 62.43, H: 5.59, O: 
31.96, % found: C: 61.2, H: 5.6, O: 31.2. 
Preparation X 
8-chloro-4-dioxolano-chroman-6-carbaldehyde (V.sub.2) 
By operating as indicated in preparation IX, and from 45 g 
(1.5.times.10.sup.-1 M) of dioxolan IV.sub.2, 31 g (yield: 84%) of 
expected product are obtained after recrystallisation in benzene. 
m.p.=133.degree. C. 
Analysis: C.sub.12 H.sub.11 O.sub.4 Cl: % calculated: C: 56.62, H: 4.32, O: 
25.12, % found: C: 55.3, H: 4.5, O: 24.6. 
Preparation XI 
8-methoxy-4-oxo-chroman-6-carbaldehyde (VI.sub.1) 
To 34 g (1.4.times.10.sup.-1 M) of dioxolan V.sub.1 in 700 cm.sup.3 of 
ethyl alcohol are added--slowly and at ambient temperature--90 cm.sup.3 of 
concentrated hydrochloric acid. The mixture is maintained for 1 hour under 
stirring then poured onto glacial water and extracted with ether. After 
recrystallisation of the solid obtained from ethyl alcohol, 26 g (yield: 
91%) of expected product are obtained (m.p.=139.degree. C.). 
Analysis: C.sub.11 H.sub.10 O4: % calculated: C: 64.10, H: 4.85, O: 31.03, 
% found: C: 64.5, H: 4.9, O: 30.1.

EXAMPLE 1 
7,8,9-trihydro-pyrano[2,3-g]indole-2-carboxylate of methyl 
To a methanol solution of sodium methylate [1.4 g of Na (6.times.10.sup.-2 
gram-atoms) in 30 cm.sup.3 of anhydrous methanol], are added, at 0.degree. 
C., 4.5 g (2.8.times.10.sup.-2 M) of 6-formyl-chroman, dissolved in 10 
cm.sup.3 of anhydrous methanol. 7.2 g (5.6.times.10.sup.-2 M) of ethyl 
azidoacetate are then poured, drop by drop, at 0.degree. C. and with 
stirring, in 10 cm.sup.3 of anhydrous methanol. After having maintained 
the temperature at 0.degree. C. for 6 hours, the reaction mixture is 
poured on glacial water and the azide is retained by filtration. 
In 30 cm.sup.3 of xylene taken to boiling point, the azide dissolved in 150 
cm.sup.3 of xylene is added with stirring. The addition terminated, 
stirring and reflux are maintained for 5 hours. After elimination of the 
xylene, the solid residue obtained is recrystallised from an isopropyl 
ether-benzene mixture and 2.7 g (yield=42%) of expected product are 
obtained. m.p.=163.degree. C. 
Analysis: C.sub.13 H.sub.13 O.sub.3 N: % calculated: C: 67.55, H: 5.62, O: 
20.75, N: 6.05, % found: C: 67.6, H: 5.7, O: 20.7, N: 6.0. 
EXAMPLE 2 
5-chloro-7,8,9-trihydro-pyrano[2,3-g]indole-2-carboxylate of methyl 
According to the process described in Example 1 and from 16 g 
(6.9.times.10.sup.-1 gram-atoms) of Na dissolved in 600 cm.sup.3 of 
anhydrous methanol, 59 g (3.times.10.sup.-1 M) of chloroformyl-chroman II 
b.sub.1 in 250 cm.sup.3 of anhydrous methanol and 77 g (6.times.10.sup.-1 
M) of ethyl azidoacetate in 100 cm.sup.3 of anhydrous methanol, the azide 
is isolated which is dissolved in 500 cm.sup.3 of xylene and added to 500 
cm.sup.3 of xylene taken to boiling point. After elimination of the xylene 
and recrystallisation from ethyl alcohol, 23 g (yield=29%) of expected 
compound are isolated. m.p. 238.degree. C. 
Analysis: C.sub.13 H.sub.12 O.sub.3 NCl: % calculated: C: 58.79, O: 18.06, 
N: 5.27, Cl: 13.34, % found: C: 58.7, O: 18.3, N: 5.3, Cl: 13.4. 
EXAMPLE 3 
5-methoxy-7,8,9-trihydro-pyrano[2,3-g]indole-2-carboxylate of methyl 
According to the process described in Example 1, and from 19 g 
(8.times.10.sup.-1 gram-atoms) of Na dissolved in 1250 cm.sup.3 of 
anhydrous methanol, 73 g (3.8.times.10.sup.-1 M) of methoxyformylchroman 
IIb.sub.2 in 50 cm.sup.3 of methanol and 98 g (7.6.times.10.sup.-1 M) of 
ethyl azidoacetate in 100 cm.sup.3 of methanol, the azide is isolated. 
After cyclization of the azide in xylene, 38 g (yield=38%) of expected 
ester are obtained. m.p.=231.degree. C. 
Analysis: C.sub.14 H.sub.15 O.sub.4 N: % calculated: C: 64.39, H: 5.74, O: 
24.49, N: 5.36, % found: C: 64.3, H: 5.8, O: 24.3, N: 5.2. 
EXAMPLE 4 
7,8,9-trihydro-pyrano[2,3-g]indole-2-carboxylic acid 
A solution of 17 g (7.4.times.10.sup.-2 M) of the product of Example 1 and 
8.3 g (1.5.times.10.sup.-1 M) of KOH in 300 cm.sup.3 of water is refluxed 
for 3 hours, 30 minutes. After return to ambient temperature, 
acidification at 0.degree. C. by 5 N hydrochloric acid, the precipitate 
obtained is filtered, washed with water up to neutrality and 
recrystallised in an ethanol-water mixture. 13.2 g (yield=83%) of expected 
acid are isolated. m.p.=228.degree. C. 
Analysis: C.sub.12 H.sub.11 O.sub.3 N: % calculated: C: 66.38, H: 5.06, O: 
22.09, N: 6.44, % found: C: 66.5, H: 5.2, O: 22.1, N: 6.4. 
EXAMPLE 5 
5-chloro-7,8,9-trihydro-pyrano[2,3-g]indole-2-carboxylic acid 
When operating is as in accordance with the process of Example 4, and from 
22.6 g (8.5.times.10.sup.-2 M) of product of Example 2 and from 14 g 
(2.6.times.10.sup.-1 M) of potassium hydroxide in 300 cm.sup.3 of water, 
20 g (yield=93%) of expected acid are obtained. m.p.=308.degree. C. 
Analysis: C.sub.12 H.sub.10 O.sub.3 NCl: % calculated: C: 57.29, H: 3.97, 
O: 19.07, N: 5.56, Cl: 14.09, % found: C: 57.1, H: 4.0, O: 19.2, N: 5.6, 
Cl: 13.7. 
EXAMPLE 6 
5-methoxy-7,8,9-trihydro-pyrano[2,3-g]indole-2-carboxylic acid 
According to the process of Example 4 and from 10 g (3.8.times.10.sup.-2 M) 
of the product of example 3 in 150 cm.sup.3 of methanol and 6.4 g 
(1.1.times.10.sup.-1 M) of potassium hydroxide in 15 cm.sup.3 of water 
taken to boiling point for 1 hour 30 mins., 9.3 g (yield=98%) of desired 
acid are isolated. m.p.=268.degree. C. 
Analysis: C.sub.13 H.sub.13 O.sub.4 N: % calculated: C: 63.18, H: 5.26, O: 
25.88, N: 5.66, % found: C: 63.1, H: 5.3, O: 26.0, N: 5.8. 
EXAMPLES 7 AND 29 
7,8,9-trihydro-pyrano[2,3-g]indole, Example 7 and 
5,6,7-trihydro-pyrano[3,2-f]indole, Example 29 
120 cm.sup.3 of distilled quinoline, 5 g (2.3.times.10.sup.-2 M) of the 
product of Example 4 and 80 mg of copper chromite are heated to 
190.degree.-195.degree. C. for 7 hours 30 mins. After return to ambient 
temperature, the catalyst is collected by filtration, the solution is 
diluted with chloroform and the quinoline is eliminated by washing with 5 
N hydrochloric acid. The chloroform phase is then washed with water up to 
neutrality, evaporated and the residue obtained is chromatographed on 
silicic acid [eluent: chloroform-hexane (2:1)v/v]. After evaporation of 
the suitable fractions of elution and recrystallisation from isopropyl 
ether, 3.3 g (yield=83%) of the desired pyrano[g]indole are isolated; 
m.p.=115.degree. C. and 0.3 g (yield=7%) of the desired pyrano[f]indole is 
isolated. m.p.=97.degree. C. 
Analysis: C.sub.11 H.sub.11 ON: % calculated: C: 76.32, H: 6.35, O: 9.23, 
N: 8.08, % found: C: 76.3, H: 6.5, O: 9.3, N: 8.0, (Example 7), C: 75.7, 
H: 6.5, O: 9.2, N: 8.0 (Example 29). 
EXAMPLE 8 
5-chloro-7,8,9-trihydro-pyrano[2,3-g]indole 
According to the process of Example 7, and from 9 g (3.6.times.10.sup.-2 M) 
of the product of Example 5 and from 0.18 g of copper chromite in 240 
cm.sup.3 of quinoline, after chromatography on silicic acid (eluent: 
chloroform) and recrystallisation from a mixture of isopropyl ether and 
hexane, 5.5 g (yield=74%) of the desired pyrano[2,3-g]indole are isolated. 
m.p. 108.degree. C. 
Analysis: C.sub.11 H.sub.10 ONCl: % calculated: C: 63.65, H: 4.81, O: 7.70, 
N: 6.74, Cl: 17.08, % found: C: 63.8, H: 4.9, O: 7.9, N: 6.8, Cl: 17.2. 
EXAMPLE 9 
5-methoxy-7,8,9-trihydro-pyrano[2,3-g]indole 
According to the process of Example 7, but with a reduced duration of 
decarboxylation (4 hours), from 12 g (4.9.times.10.sup.-2 M) of the 
product of Example 6, 0.24 g of copper chromite and 240 cm.sup.3 of 
quinoline, after chromatography on silicic acid (eluent: chloroform) and 
recrystallisation from benzene, 6 g (yield=60%) of expected product are 
isolated. m.p. 138.degree. C. 
Analysis: C.sub.12 H.sub.13 O.sub.2 N: % calculated: C: 70.96, H: 6.40, O: 
15.74, N: 6.89, % found: C: 71.0, H: 6.4, O: 15.8, N: 6.8. 
EXAMPLE 10 
7,8,9-trihydro-pyrano[2,3-g]indole-3-carbaldehyde 
In 0.3 g (2.times.10.sup.-3 M) of phosphorus oxytrichloride in 0.12 g 
(1.6.times.10.sup.-3 M) of N,N-dimethylformamide, 10 cm.sup.3 of 
1,2-dichloroethane then 0.27 g (1.5.times.10.sup.-3 M) of the product of 
Example 7 dissolved in 10 cm.sup.3 of 1,2-dichloroethane are poured at 
5.degree. C. The mixture is maintained at 5.degree. C. for 2 hours 30 
mins. then refluxed for 30 mins. After cooling, 1.2 g (9.times.10.sup.-3 
M) of trihydrated sodium acetate dissolved in 10 cm.sup.3 of water are 
added and taken to boiling point for 15 mins. After return to ambient 
temperature, neutralisation, washing with water, 0.2 g (yield=64%) of the 
desired aldehyde is obtained--after recrystallisation from ethanol--m.p. 
232.degree. C. 
Analysis: C.sub.12 H.sub.11 O.sub.2 N: % calculated: C: 71.66, H: 5.46, O: 
15.90, N: 6.96, % found: C: 71.6, H: 5.4, O: 15.9, N: 7.0. 
EXAMPLE 11 
5-chloro-7,8,9-trihydro-pyrano[2,3-g]indole-3-carbaldehyde 
From 0.3 g (2.times.10.sup.-3 M) of phosphorus oxytrichloride, 0.12 g 
(1.6.times.10.sup.-3 M) of N,N-dimethylformamide in 10 cm.sup.3 of 
1,2-dichloroethane and 0.3 g (1.45.times.10.sup.-3 M) of chlorinated 
pyrano[g]indole prepared according to Example 8, 0.1 g (yield=29%) of the 
desired aldehyde, m.p.=214.degree. C., is obtained after chromatography on 
silicic acid [eluent: chloroform-acetone (3:1) v/v] and recrystallisation 
from a mixture of benzene and hexane. 
Analysis: C.sub.12 H.sub.10 O.sub.2 NCl: % calculated: C: 61.18, H: 4.24, 
O:13.57, N: 5.94, C: 15.04, % found: C: 59.8, H: 4.3, O: 13.8. 
EXAMPLE 12 
5-methoxy-7,8,9-trihydro-pyrano[2,3-g]indole-3-carbaldehyde 
According to the process of Example 10 and from 0.3 g (1.47.times.10.sup.-3 
M) of methoxylated pyrano[g]indole of Example 9, 0.11 g (yield=31%) of the 
expected aldehyde, m.p.=107.degree. C., is isolated after chromatography 
on silicic acid (eluent: chloroform-acetone (3:1) v/v) and 
recrystallisation from benzene. 
Analysis: C.sub.13 H.sub.13 O.sub.3 N: % calculated: C: 67.55, H: 5.62, O: 
20.75, N: 6.05, % found: C: 67.1, H: 5.6, O: 20.8, N: 6.0. 
EXAMPLE 13 
3-(7,8,9-trihydro-pyrano[2,3-g]indolyl)-N,N-dimethylglyoxamide 
In 1 g (5.7.times.10.sup.-3 M) of pyrano[g]indole prepared according to 
Example 7 in 25 cm.sup.3 of anhydrous ether, is poured--in a current of 
nitrogen and at 0.degree. C.--a solution of 1 cm.sup.3 of oxalyl chloride 
in 5 cm.sup.3 of anhydrous ether. The mixture is maintained for 30 mins. 
at 0.degree. C. then refluxed for 15 mins; after cooling to 0.degree. C. a 
solution of dimethylamine is rapidly added until the reaction medium is 
basic. It is left for 12 hours at ambient temperature, the precipitate 
which appears is filtered and is recrystallised from methanol. 1.1 g 
(yield=70%) of the desired derivative are isolated. m.p.=290.degree. C. 
Analysis: C.sub.15 H.sub.6 O.sub.3 N.sub.2 : % calculated: C: 66.20, H: 
5.87, N: 10.28, % found: C: 65.3, H: 6.0, N: 10.0. 
EXAMPLE 14 
3-(7,8,9-trihydro-pyrano[2,3-g]indolyl)-N,N-dimethylmethylamine 
A mixture of 0.46 g (5.7.times.10.sup.-3 M) of 37% w/v formaldehyde, 0.65 g 
(5.7.times.10.sup.-3 M) of 40% w/v dimethylamine and 1 g 
(5.7.times.10.sup.-3 M) of product of Example 7 in 30 cm.sup.3 of 
methanol, is taken to boiling point for 3 days. After evaporation of the 
solvent, dissolution of the oily product obtained in ethyl acetate, it is 
treated with 5 N hydrochloric acid, washed with chloroform and the aqueous 
phase is rendered alkaline by addition of 20% w/v sodium hydroxide. It is 
then extracted with ether and 0.77 g (yield=58%) of oily product is 
isolated (free base). 
0.8 g (3.4.times.10.sup.-3 M) of picric acid dissolved in 15 cm.sup.3 of 
ethanol is added at ambient temperature, the reaction mixture is stirred 
for 12 hours, the precipitate formed is filtered, washed with ethanol and 
1.4 g (yield=93%) of picrate is thus obtained m.p.=160.degree. C. 
Analysis: C.sub.20 H.sub.21 O.sub.8 N.sub.5 : % calculated: C: 52.31, H- 
4.57, O: 27.86, N: 15.24, % found: C: 52.3, H: 4.5, O: 27.9, N: 15.2. 
The preparation of the products of Examples 15 and 16 is given in the modi 
operandi of Examples 17 and 18 respectively. 
EXAMPLE 17 
5-methoxy-9-oxo-7,8-dihydro-pyrano[2,3-g]indole-2-carboxylate of methyl 
To 0.7 g (3.times.10.sup.-2 gram-atoms) of Na in 30 cm.sup.3 of anhydrous 
methanol are added 3 g (1.2.times.10.sup.-2 M) of dioxolan V.sub.1 and 3.7 
g (2.9.times.10.sup.-2 M) of ethyl azidoacetate in 10 cm.sup.3 of 
anhydrous methanol. The mixture is maintained for 7 days at 0.degree. C. 
and extracted with ether. The azide obtained is then dissolved in 70 
cm.sup.3 of xylene taken to boiling point for 3 hours and the cyclized 
product thus obtained (Example 15) is treated after dissolution in 50 
cm.sup.3 of ethanol with 5 cm.sup.3 of concentrated hydrochloric acid. The 
mixture is left for 18 hours and 0.52 g (yield=16%) of the desired ester 
is isolated after recrystallisation from benzene. m.p. 188.degree. C. 
Analysis: C.sub.14 H.sub.13 O.sub.5 N: % calculated: C: 61.12, H: 4.72, O: 
29.06, N: 5.08, % found: C: 60.9, H: 4.6, O: 29.2, N: 5.1. 
EXAMPLE 18 
5-chloro-9-oxo-7,8-dihydro-pyrano[2,3-g]indole-2-carboxylate of methyl 
From 26 g of dioxolan aldehyde V.sub.2 and according to the process 
described for preparing the preceding product, the product of Example 16 
is obtained, after cyclization of the azide (reflux time 8 hours) which, 
after hydrolysis, gives 15 g (yield=54%) of the desired ester, 
m.p.=194.degree. C. (Recrystallisation from benzene). 
Analysis: C.sub.13 H.sub.10 O.sub.4 NCl: % calculated: C: 55.85, H: 3.57, 
O: 22.88, N: 5.00, Cl: 12.68, % found: C: 55.9, H: 3.7, O: 22.8, N: 5.0, 
Cl: 12.8. 
EXAMPLE 19 
5-methoxy-9-oxo-7,8-dihydro-pyrano[2,3-g]indole-2-carboxylic acid 
By using the method of saponification described for the preparation of the 
product of Example 4 and from 34 g (1.2.times.10.sup.-1 M) of the product 
of Example 17 and 14 g (2.5.times.10.sup.-1 M) of potassium hydroxide in 
700 cm.sup.3 of water, 30 g (yield=93%) of expected acid are isolated. 
m.p. 312.degree. C. 
Analysis: C.sub.13 H.sub.11 O.sub.5 N: % calculated: C: 59.80, H: 4.21, O: 
30.62, N: 5.36, % found: C: 59.0, H: 4.2, O: 30.8, N: 5.3. 
EXAMPLE 20 
5-chloro-9-oxo-7,8-dihydro-pyrano[2,3-g]indole-2-carboxylic acid 
According to the process of Example 19 and from 26 g (9.3.times.10.sup.-2 
M) of the product of Example 8, 27 g (yield=90%) of expected acid are 
obtained, m.p. 227.degree.-230.degree. C. 
Analysis: C.sub.12 H.sub.8 O.sub.4 NCl: % calculated: C: 54.27, H: 3.01, O: 
24.08, N: 5.27, % found: C: 54.2, H: 3.6, O: 24.7, N: 5.0. 
EXAMPLE 21 
5-methoxy-9-oxo-7,8-dihydro-pyrano[2,3-g]indole 
According to the method of decarboxylation used for obtaining the 
pyranoindole of Example 7 and from 31 g (1.2.times.10.sup.-1 M) of the 
product of Example 19 and from 0.77 g of copper chromite in 500 cm.sup.3 
of quinoline, 14 g (yield=54%) of expected product are obtained (m.p. 
123.degree. C.) after 13 hours of reaction, chromatography on silicic acid 
(eluent: chloroform) and recrystallisation from benzene. 
Analysis: C.sub.12 H.sub.11 O.sub.3 N: % calculated: C: 66.38, H: 5.06, O: 
22.09, N: 6.44, % found: C: 66.4, H: 5.1, O: 22.2, N: 6.3. 
EXAMPLE 22 
5-methoxy-9-oxo-7,8-dihydro-pyrano[2,3-g]indole-3-carbaldehyde 
According to the modi operandi described for the preparation of the product 
of Example 10 and from 0.4 g (1.8.times.10.sup.-3 M) of the product of 
Example 21, 0.19 g (yield=42%) of expected product is obtained 
(m.p.=236.degree. C.) after chromatography on silicic acid [eluent: 
chloroform-acetone (3:1) v/v] then recrystallation from a mixture of 
ethanol-benzene-hexane. 
Analysis: C.sub.13 H.sub.11 O.sub.4 N: % calculated: C: 63.70, H: 4.48, O: 
26.09, N: 5.71, % found: C: 63.4, H: 4.6, O: 25.8, N: 5.7. 
The products of Examples 23 to 28 given in Table 1 hereinbelow are prepared 
according to the modi operated described hereinabove. 
EXAMPLE 30 
5,6,7-trihydro-pyrano[3,2-f]indole-3-carbaldehyde 
According to the process of Example 10 and from 0.2 g (1.3.times.10.sup.-3 
M) of phosphorus oxytrichloride, 0.09 g (1.2.times.10.sup.-3 M) of 
N,N-dimethylformamide, 0.2 g (1.1.times.10.sup.-3 M) of the product of 
Example 29 and 1 g (7.times.10.sup.-3 M) of trihydrated sodium acetate, 
0.075 g (yield=31%) of expected product (m.p. 195.degree. C.) is isolated 
after recrystallisation from benzene. 
Analysis: C.sub.12 H.sub.11 O.sub.2 N: % calculated: C: 71.66, H: 5.46, O: 
15.90, N: 6.96, % found: C: 71.8, H: 5.5, O: 15.9, N: 7.0. 
The product of Example 31 given in Table II hereinbelow is prepared 
according to the modi operandi described hereinabove. 
The compounds according to the invention essentially have anti-ulcerous, 
anti-inflammatory and antalgic effects. They are particularly useful as 
anti-ulcerous, anti-inflammatory and antalgic agents in the treatment of 
ulcers, pain and inflammations. Certain products further present 
anti-aggregating and anti-thrombotic effects useful in the treatment of 
diseases associated with circulatory disorders. 
The pharmacological tests carried out particularly with regard to toxicity, 
the ulcers provoked by aspirin and serotonin, and the anti-inflammatory 
and antalgic effects, are summarised hereinafter. The methods used are 
recalled hereinafter. 
Ulcer provoked by aspirin 
The experiment is carried out on male Wistar rats weighing 180 to 200 g. 
At t=0 the rats are made to fast and a first administration of the product 
to be tested, at a dose of 100 mg/kg, is made IP. 
At t=18 hours, 2 ml of an ulcer-forming suspension with 192 mg of 
aspirin/kg are administered per os then a second IP administration of the 
product to be tested, at a dose of 100 mg/kg, is made. 
At t=22 hours, the animals are sacrificed and the ulcers are marked as 
follows: 
small punctiform ulcers: mark 1 
more extensive ulcers: mark 3 
very expensive or very deep ulcers: mark 9 
The results relative to the inhibition of the ulcers provoked by aspirin 
are given in Table III hereinafter. 
Ulcer provoked by serotonin 
The technique used is the one described by Hashizume, in Arch. Int. 
Pharmacodyn, 236, 96-108, (1978). 
The experiment is carried out on 3 batches of male Sprague-Dawley rats. 
Each batch includes 20 animals. 
The first batch constitutes the controls, the second is treated with 
Carbenoxolone, the third is treated with the product to be tested. 
The animals are made to fast 24 hours before the experiment. 
At t=0, 
the product to be tested is administered by the IP route to the third 
batch, 
100 mg/kg of Carbenoxolone are administered per os to the second batch. 
At t=+10 mins., a sub-cutaneous injection is made of serotonin at 60 mg/kg 
in the three batches. 
At t=+250 mins., the animals are sacrificed. The stomachs are removed and 
spread out and the ulcers are marked as follows: 
small ulcer +=1 
average ulcer ++=3 
large ulcer +++=9 
The results relative to the inhibition of the ulcers provoked by serotonin 
are given in Table IV hereinbelow with the doses of the products tested. 
The techniques relative to the anti-inflammatory effects (oedema caused by 
carragenine) and antalgic effects (cramping) which were used are the 
conventional techniques described in the prior art. The results obtained 
are given in Table III hereinbelow. 
Table III hereinbelow deals with the LD.sub.50 and with the inhibition of 
the ulcers caused by aspirin, the inhibition of the oedema provoked by 
carragenine and cramping (the products to be tested being, in the latter 
two cases, administered by the IP route at a dose equal to one tenth of 
the LD.sub.50 IP). 
According to the invention, a therapeutic composition is recommended, 
characterised in that it contains, in association with a physiologically 
acceptable excipient, a pharmaceutically effective dose of a pyrano-indole 
derivative according to the invention or one of its non-toxic acid 
addition salts. 
In clinic, excellent results have been obtained in man, in the treatment of 
ulcers with the products of Examples 7,8,14,19, 21 and 23, in the 
treatment of pain with the product of Example 6, and in the treatment of 
oedemas with the products of examples 4, 5, 9 and 24. 
The dosage of recommended for the treatment of gastric or duodenal ulcers, 
in the male adult, is 50 mg to 1500 mg per day, by oral administration. 
Such a dose may be divided and taken 2 to 5 times per day. 100 mg to 1000 
mg of active ingredient are preferably administered by the oral route 
divided 4 or 5 times a day, for at least 2 to 3 weeks. 
TABLE I 
__________________________________________________________________________ 
##STR10## 
Melting point 
Example 
Code No 
X R.sub.1 R.sub.2 
R.sub.3 R.sub.4 
.degree.C. 
__________________________________________________________________________ 
1 -- CH.sub.2 
H COOCH.sub.3 
H H 163 
2 -- CH.sub.2 
H COOCH.sub.3 
H Cl 238 
3 -- CH.sub.2 
H COOCH.sub.3 
H OCH.sub.3 
231 
4 231 CH.sub.2 
H COOH H H 228 
5 258 CH.sub.2 
H COOH H Cl 308 
6 336 CH.sub.2 
H COOH H OCH.sub.3 
268 
7 275 CH.sub.2 
H H H H 115 
8 338 CH.sub.2 
H H H Cl 108 
9 337 CH.sub.2 
H H H OCH.sub.3 
138 
10 -- CH.sub.2 
H H CHO H 232 
11 -- CH.sub.2 
H H CHO Cl 214 
12 -- CH.sub.2 
H H CHO OCH.sub.3 
107 
13 -- CH.sub.2 
H H 
##STR11## 
H 290 
14 333 CH.sub.2 
H H 
##STR12## 
H --.sup.(a) 
15 -- 
##STR13## 
H COOCH.sub.3 
H OCH.sub.3 
--.sup.(b) 
16 -- 
##STR14## 
H COOCH.sub.3 
H Cl --.sup.(b) 
17 -- CO H COOCH.sub.3 
H OCH.sub.3 
188 
18 -- CO H COOCH.sub.3 
H Cl 194 
19 266 CO H COOH H OCH.sub.3 
312 
20 -- CO H COOH H Cl 227-230 
21 205 CO H H H OCH.sub.3 
123 
22 -- CO H H CHO OCH.sub.3 
236 
23 598 CNOH H H H OCH.sub.3 
222 
24 599 CHOH H H H OCH.sub.3 
147 
25 -- CHNH.sub.2 
H H H OCH.sub.3 
.sup.(b) 
26 -- CO H H CH.sub.2 N(CH.sub.3).sub.2 
OCH.sub.3 
121 
27 -- CH.sub.2 
(CH.sub.2).sub.3 N(CH.sub.3).sub.2 
H H Cl 69 
28 -- CH.sub.2 
CH.sub.3 
H H Cl 152 
__________________________________________________________________________ 
Note: 
.sup.(a) free base ia an oily product, corresponding picrate melts at 
160.degree. C.; 
.sup.(b) Oil. 
TABLE II 
______________________________________ 
##STR15## 
Melting point 
Example Code No X R.sub.3 
R.sub.4 
.degree.C. 
______________________________________ 
29 -- CH.sub.2 H H 97 
30 -- CH.sub.2 CHO H 195 
31 -- CH.sub.2 H Cl 117 
______________________________________ 
TABLE III 
__________________________________________________________________________ 
Aspirine 
Carragheenine 
DL.sub.50 
induced ulcer 
oedema Cramping 
Example 
Code No 
mg/kg I.P. 
% inhibition 
% inhibition 
% inhibition 
__________________________________________________________________________ 
21 205 600 60 49 37 
4 231 600 11 35 36 
5 258 300 28 30 35 
7 275 750 46 -- 14 
19 266 &gt;1000 49 -- -- 
14 333 180 47.5 22 67 
6 336 &gt;800 23 -- 66 
9 337 650 51 39 41 
8 338 900 42.5 33 26 
23 598 (DL.sub.o &gt;800) 
40 52 51 
24 599 1000 -- 40 60 
__________________________________________________________________________ 
TABLE IV 
______________________________________ 
Serotonine 
Dosis ulcer 
Example Code No mg/kg IP % inhibition 
______________________________________ 
7 275 75 64 
8 338 45 75 
21 205 60 87 
23 598 92 52 
Carbenoxolone 
-- 60 64 
______________________________________ 
##STR16##