CA2173158C - Anthracycline disaccharides, process for their preparation, and pharmaceutical compositions containing them - Google Patents

Abstract

The present invention is referred to compounds of gen- eral formula (I) and (II), respectively their pharmaceutically acceptable salts, the process for their preparation, and the pharmaceutical compositions containing them.

Description

Anthracycline disaccharides, process for their preparation, and pharmaceutical compositions containing them Field of the invention The present invention is referred to compounds of general formula (I) and (II), respectively p OH O

TO~
R~ O OH V

O
R5 R4 ~I~ R3 (II) where:
R is H or OH or the ORS group where R~ - CHO or COCH3 or the acylic residue of a carboxylic acid containing up to 6 carbon atoms;
R1 is H or OH or OCH3;
R2 is H or F;
R3 is H or OH;
R4 and R5, identical or different, are each H or OH or NH2;
and bond symbol (~..) indicates that substituents R3, R~, and R5 may be either in axial or equatorial position; and their pharmaceutically acceptable salts having anticancer properties.
As may be seen in the above formulas, compound:a (I) and (II) differ 'C H"R _ z~ 7~~ ~~

exclusively in the apace arrangement of the glycosidic groups and.
therefore. map be represented by formula iA) 0 off , o 'C H2R
(A) r where symbol ice) indicates that the second carbohydrate residue may be bound to carbon atom 4' of the first sugar either in axial or in equatorial position.
The present invention is also referred to the process for the preparation of said compounds. their phaz~aceuti.cally acceptable salts.
and the pharmaceutical compositions caata~ n~ ng ~th ~..
State of the art Daunorubicir_ and daaorubicin are well-known ~atibiotics that are currently used in the clinical practic= for the treatment of a variety of solid tumours and leukaemia (F. Arc3mone in "Doxorubicin: Anticancer Antibiotics". A.C. Sartorelli. Ed.. Academic Press. N. Y.. 1981).
A~NDED SHEEN

- 2bis -Compounds having a structure similar to~those described in the present application buk presenting only one glycosidic group are described in EP-457215, WO 80/00305 ana WO 90/'07589. Compounds showing two or more sugar soieties wherein the sugar directly linked to the aglycone moiQty is amino-substituted ire descried for example in The Journal of Antibiotics p. 1720-1730 Nov. 93; Tetrahedron Vol. 37, No.
24, 4219-422E (1981): flE 27 51 395; Carbohydrate Research, 228. 171-90 !1992) and DE-3641833.
Compounds h~-ing three glycoside moieties, and for which no activity data are repcrted, are described in WO 92/07862.
As known. h.awever, the severe side effects caused by the anticancer agents used nt present impose limits on the use of same in a good number of patients ~aho, otbEr~aise. Would benefit from the treatment. Moreover.
AMENDED SHEET

2173158 a remarkable advances are needed in the treatment of some important solid tumours, e.g. pulmonary and ovarial, that do not adequately respond to any current treatment.
It follows that there is an urgent need for the coming onto the market of drugs highly selective in their inhibitory action against the proliferation of diseased cells compared with the normal ones.
Detailed description of the invention It is an object of the present invention to provide new anticancer compounds, in particular anthracycline analogues, in which the carbohydrate portion consists of a disaccharide residue.
It has surprisingly been found that the claimed anthracycline disaccharides, in which the sugar directly bound to aglycone never contains amino groups, exhibit higher anticancer acaivity and selectivity than the anthracycline previously known. It is worth noting that in the known anthracyclines, having similar structure and which contain two carbohydrate residues, the sugar bound to aglycone always contains a free or substituted amino group.
The compounds according to the present invention are the compounds of general formula {I) and (II;, as reported above, and their pharmaceutically acceptable salts where R, R1, R2, R3, R4, and R5 are as described above.
The present invention is also referred t:o pharmaceutical compositions containing said compounds, or salts thereof with pharmaceutically acceptable acids, preferably hydrochloric acid.
Particularly preferred are the following compounds:
a) 7-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-a-L-lyxo-exopyranosyl)-a-L-lyxo-exopyranosyll daunorubicinone chlorhydrate;
b) '7-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-a-L-lyxo-exopyranosyl)-n-A

~1~ ~~,5 L-arabino-exopyranosyl] daunorubicinone chlorhydrate;
c) '7-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-a-L-lyxo-exopyranosyl)-a-L-lyxo-exopyranosyl] doxorubicinone chlorhydrate;
d) '7-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-a-L-lyxo-exopyranosyl)-a-L-arabino-exopyranosyl] doxorubicinone chlorhydrate;
e) '7-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-a-L-lyxo-exopyranosyl)-a-L-arabino-exopyranosyl]-4-demethoxy-daunorubicinone chlorhydrate;
f) '7-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-a-L-lyxo-exopyranosyl)-a=
L-lyxo-exopyranosyl]-4-demethoxy-daunorubicinone chlorhyrate;
g) 7-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-a-L-lyxo-exopyranosyl)-a-L-lyxo-exopyranosyl]-4-demethoxy-doxorubicinone chlorhydrate;
h) '7-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-a-L-lyxo-exopyranosyl)-a-L-arabino-exopyranosyl]-4-demethoxy-doxorubicinone chlorhydrate;
i) '7-0-[2,6-dideoxy-4-0-(2,3,4,6-tetradeoxy-4-amino-a-L-erythro-exopyranosyl)-a-L-lyxo-exopyranosyl] daunorubicinone chlorhydrate;
j) ~-0-[2,6-dideoxy-4-0-(2,3,4,6-tetradeoxy-4-amino-a-L-erythro-exopyranosyl)-a-L-lyxo-exopyranosyl]-4-demethoxy-daunorubicinone chlorhydrate;
k) 7-0-[2,6-dideoxy-4-0-(2,3,4,6-tetradeoxy-4-amino-a-L-erythro-exopyranosyl)-a-L-lyxo-exopyranosyl] doxorubicinone chlorhydrate;
1) '7-0-[2,6-dideoxy-4-0-(2,3,4,6-tetradeoxy-4-amino-a-L-erythro-exopyranosyl)-a-L-lyxo-exopyranosyl]-4-demethoxy-doxorubicinone chlorhydrate;
m) '7-0-[2.6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-a-L-lyxo-exopyranosyl)-a-L-lyxo-exopyranosyl]-4-demethoxy-8-fluoro-daunorubicinone chlorhydrate;
n) '7-0-[2.6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-a-L-lyxo-exopyranosyl)-a-L-lyxo-exopyranosyl]-4-demethoxy-8-fluoro-doxorubicinone chlorhydrate.
The compounds of general formula (I) and (II) can be prepared by a -5- ~ 21'~315g process consisting of the following steps:
a) condensation of a compound of formula (III) (III) OH

R ~ O OH OH
where R1 and R2 are as defined above and R6 is H or the ORS group where R7 is a protective group for an alcoholic function, preferably selected among the acetyl-, dimethylterbutylsilyl- or prmethoxyphenyldiphenylmethyl- groups, with a compound of formula (IV) or (V) X
r~

_-m rc9 (IV) ('V) where R8 is H or a protected -OH group, preferably p-nitrobenzoate; R9 and R10, identical or different, are each H or a protected OH group, preferably p-nitrobenzoate or a protected N'H2 group, preferably trifluoroacetamide or allylcarboxyamide and X :is a group capable of generating, under the condensation conditions, a stable carbo-cation that may bind itself to a hydroxyl group in position C-'7 of the compound of formula (III), said group X being conveniently selected among the groups used in glycosidation reactions, e.g. a halogen such as chlorine or ~1 O OH p bromine, preferably chlorine, or a p-nitrobenzo~-loxy group. Compounds of formula (VI) or (VII) are thus obtained:
II
\ OH C H2R 6 R~ O OH O
O
O / ,r ( v1 ) R10 Rg O OH O
_ Il I 11 H2 Rfi R ~ O OH O
O
R8 !vTy) ~O
~0 R9 where R1, R2, R6, R8, R9. R10 and symbol (.~ are as defined above;
b) one or more reactions of removal of the protective groups of OH
and/or NH2 functions from compounds of formula (VI) and (VII) to give compounds of formula (I) and (II), where R, R1, R2, R3, R4, R5 and symbol (~ are as defined above;
c) conversion, if any, of the aforesaid glycosides of formula (I) and (II) into a pharmaceutically acceptable salt thereof, preferably chlorhydrate.
The reaction conditions for the glycosidation of a compound of formula ~'1"~3.~~8 -(III) with a compound of formula (IV) or (V) to give a compound of formula (VI) or (fII~ may vary depending on the type of substituents present i~ tie compounris of formula ( If ) ar (V) .
Glycosidatioa is carried out in an inert arganic solvent in the presence of a condensing agent.
The condensing agents used are. e.g., silver triftnoromethane sulphonate.
silver perch3orate, fixtures of mercury Gti.de and mercury bromide, boron halides . tit3aium or tin tetrachloride or ion. Eschange resins , such as Amberlite ~, silver triflate, trimethylsilyltriflate, p-toluensulphonic acid, trifluoroacetic acid.
Glycosidation is preferably carried out with 1.:1 to 1:3 molar ratios in an inert organic solvent, such as for example benzene, toluene, ethyl ether, tetrahydrofuran, dioxane, chloroform, methylene chloride or dichloroethane and ~ctures thereof.
The reaction tempera~are may range from -~+0'C to ~0'C, preferably from -20'C to 20'C, and tre reaction time from 15 min to 3 hrs.
The reaction mixture may include a cehydrating substance. such as an activated molecular sieve.
In the course of +3~e reaction or at the reaction end, the reaction mixture may be added with an organic base, such as pyridine, collidine.
N.N-dimethyiaminopyridine, triethylaaine or 1.8-bis-(dimethylamino) naphthalene.
According to the present invention, the removal of the protective groups for OH and/or NH2 functions from compounds of far~u3a (VI) and (VII) to give compounds of formula (I) may be carristl out under different conditions depending on the type of protective ~rua:p used.
When R9 and/or R10, Ldentical or different. ;~~e each a protected NH2 group such as trifluoroacetamide or a protected- OH group such as p ' nitrobenzoate, and/rr R8 is a prmtected ~g group such as p ~IpED SHEET

nitrobenzoate, and/or R6 is a protected OH group such as acetate, deprotection reactions are carried out in a polar solvent, such as water, methanol, ethanol, pyridine, dimethylformamide or mixtures thereof and in the presence of an inorganic base, in a stoichiometric amount or in excess of the stoichiometric, such as sodium, potassium, lithium or barium hydroxide or carbonate.
The reaction temperature may range from 0°C to 50°C and the reaction time from 3 hrs to 48 hrs.
When R9 and/or R10 are each a protected NH2 group such as allylcarboxyamide, deprotection is carried out in an inert solvent and in the presence of a metal complex such as tetrakis(triphenylphosphine)palladium, as disclosed, e.g., in Tetrahedron Letters, 30, 3773 (1989), or tetracarbonyl nickel, as disclosed, e.g., in J. Org. Chem., 38. 3233 (1973).
When R6 is a protected OH group such as dimethylterbutylsilylether, deprotection is carried out in an inert solvent and in the presence of tetrabutylammonium fluoride, as disclosed, e.g. in J. of Antibiot., 37, 853 (1984).
When R6 is a protected OH group such as p-methoxyphenyldiphenylmethylether, deprotection is carried out in an acid medium, e.g. in aqueous acetic acid, as disclosed, e.g. in J. Org.
Chem., 42, 3653 (1977).
Compounds of formula (III) are either known or may be prepared according to methods and processes known in organic chemistry, as disclosed, e.g.
in Gazz. Chim. Ital., 114, 517 (1984), in Bull. Chem. Soc. Jpn., 59, 423 (1986), and in Italian Patent No. 1241927. Compounds of formula (IV) or (V) are either known or may be prepared WO 95109173 217 31 ~ 8 P~~~4103201 _ 9 _ according to methods and processes for the synthesis of disaccharides known in organic chemistry [J. Carbohydr. Chem., 10, 833 (1991);
Carbohydr. Res.. 74, 199 (1979); Carbohydr. Res.. 20$, 111 (1980);
Tetrahedron, 46, 103 (1990)].
Alternatively, if so desired, anthracycline glycosides of formula (I) and (II), where R1, R2, R3, R4, R5 are as defined above and R is an OH group, may be prepared from glycosides of formula (I) and (II) or from pharmaceutically acceptable salts thereof, where R1, R2. R3, R4, R5 and symbol (wv~.) are as defined above and R is H, by bromination of the carbon in position 14 with bromine in chloroform followed by hydrolysis.
at room temperature for a period of 48 hrs, of the resulting 14-bromoderivatives with sodium formate.
If so desired, glycosides of formula (I) and (II.) may be converted into their pharmaceutically acceptable salts, e.g. chlorhydrates, by treatment with hydrochloric acid in methyl alcohol.
The present invention also relates to pharmaceutical compositions containing, as active ingredient. a compound of formula (I) or (II) or a pharmaceutically acceptable salt thereof combined with a pharmaceutically acceptable diluent or carrier.
:according to the present invention, a therapeutically effective dose of a compound of formula (I) or (II) is combined with an inert carrier.
The compositions may be formulated in a conventional manner using common carriers.
The claimed compounds are useful for the therapeutic treatment on humans and other mammals. In particular, said compounds are good anticancer agents when administered in therapeutically effective doses.
The following examples illustrate the present invention in more detail.

~1 Example 1 '7-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-a-L-lyxo-exopyranosyl)-a-L-lyxo-exopyranosyl]-4-demethoxy-daunorubicinone chlorhydrate (compound of formula II, R~R1=R2=H, R3=R5=OH, R4=NH2).
A mixture of 4-demethoxydaunorubicinone (compound of formula III, R1=R2=R6=H) (300 mg, 0.81 mmol) and 2,6-dideoxy-4-0-(2,3,6-trideoxy-4-0-p-nitrobenzoyl-3-trifluoroacetamido-a-L-lyxo-exopyranosyl)-3-0-p-nitrobenzoyl-a-L-lyxo-exopyranosyl-p-nitrobenzoate (compound of formula =p-IV, R3=R5=p-nitrobenzoyl-oxy-, R4=trifluoroacetamido-. X
nitrobenzoyloxy-) (600 mg, 0.'72 mmol) in methyl chloride ('72 ml) and ethyl ether (24 ml) in the presence of molecular sieves (A4) at -20°C
was treated with trimethylsilyltriflate (266 ul; 1.44 mmol). The reaction mixture was stirred for 1 hr, then it was diluted with methylene chloride, washed with a saturated sodium bicarbonate solution, and evaporated to dryness. The residue was separated by chromatography on silica gel (eluent CH2C12-EtOH, 99/1) yielding 360 mg of '7-0-[2,6-dideoxy-4-0-(2,3.6-trideoxy-4-0-p-nitrobenzoyl-3-fluoroacetamido-a-L-lyxo-exopyranosyl)-3-0-p-nitrobenzoyl-a-L-lyxo-exopyranosyl]-4-demethoxydaunorubicinone (compound of formula VII, R1=R2=R6=H, R8=R10=p nitrobenzoyloxy-. R9=trifluoroacetamido-).
A protected diglycoside suspension of compound of formula (VII) (R1=R2=R6=H, R8=R10=p-nitrobenzoyloxy-, R9=trifluoroacetamido-) (120 mg;
0.11 mmol) in 1~.6 ml of a 0.1 M solution of Ba(OH)2 in H20/MeOH, 1/l, was maintained under stirring at room temperature for a period of 3 hrs.
The reaction mixture was neutralized with a 0.2 M potassium bisulphate solution and extracted with chloroform; the organic extracts were collected together, dried over anhydrous sodium sulphate, evaporated to dryness, and taken up with 0.002 M HC1 solution. The acid aqueous _ ~1 _ solution was washed with chloroform and freeze-dried to give 62 mg of the desired product (compound of formula II, (R=R1=R2=H, R3=R5=OH, R4=NH2).
Yield 39%.
The NMR data obtained are reported below:
1H-NMR (DMSO-d6), d 1.05 (d,3H), 1.15 (d,3H)" 1.5-1.95 (m,4H), 2.1 (m,2H). 2.25 (s.3H), 2.95 (dd.2H). 3.55 (s,2H), 3.8 (m,lH). 3.95 (m,lH), 4.15 (q,lH). 4.35 (q,lH). 4.6 (d,lH). 4.9 (bs.2H), 5.25 (bs.lH), 5.35 (d,lH). 5.55 (s.lH). x.95 (bs.2H), 8.25 (bs,2H).
According to an analogous process, also the following compounds of formula (I) and (II) were obtained:
'7-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-a-L-lyxo-exopyranosyl)-a-L-lyxo-exopyranosyl] daunorubicinone chlorhydrate (compound of formula II, R=R2=H, R1=OCH3, R3=R5=OH. R4=NH2).
1H-NMR (DMSO-d6), a 1.05 (d.3H), 1.15 (d,3H), 1.35-2.15 (m,6H). 2.25 (s.3H). 2.95 (dd.2H), 3.55 (bs.2H). 3.8 (m,lH), 3.95 (s.3H). 4.05-4.2 (m+q,2H). 4.35 (q,lH), 4.9 (bs.2H), 5.25 (d,lH), 7.65 (m,lH), 7.9 (d,2H).
'7-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-a-L-lyxo-exopyranosyl)-a-L-arabino-exopyranosyl] daunorubicinone chlorhydrate (compound of formula I; R=R2=H, R1=OCH3. R3=R5=OH. R4=NH2).
1H-NMR (DMSO-d6), 8 1.13 (d.3H), 1.15 (d,3H), 1.45-1.85 (m.4H), 2:05 (m.2H) , 2.15 (s,3H) , 2.8'7 (dd,2H) , 2.98 (m,lH) , 3.5 (m.lH) , 3.6 (m.lH) , 3.85 (q,lH), 3.9 (q.lH). 3.9 (s.3H). 4.84 (m.a>.H), 5.13 (bs.lH). 5.28 (s,lH), 5.32 (d.lH), 5.55 (s,lH). 7.55 (m, 1H). '7.8 (m.2H).
~-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-a-L-lyxo-exopyranosyl)-a-L-arabino-exopyranosyl]-4-demethoxy-daunorubicinone chlorhydrate (compound of formula I; R=R1=R2=H. R3=R5=OH, R4=NH2).
1H-NMR (DMSO-d6), d 1.1 (d,3H). 1.2 (d,3H), 1.5-1.95 (m,4H). 2.05-2.2 (m,2H) , 2.25 (s,3H) , 2.95 (dd,2H) , 3.1 (t,lH), :;.4 (m,lH) , 3'6 (bs.lH) , 3.65 (m.lH), 3.85-4.00 (q+q,2H), 3.9 (m.lH). 4.95 (d.lH), 5.2 (d,lH), 5.4 (bs.2H), 5.'7 (s,lH). 7.95 (m.2H), 8.25 (m. 2H).

Claims (20)

Claims

1. Compounds of general formula (I) and (II), respectively where:
R is H or OH or the OR7 group where R7 = CHO or COCH3 or the acylic residue of a carboxylic acid containing up to 6 carbon atoms;
R1 is H or OH or OCH3;
R2 is H or F;
R3 is H or OH;
R4 and R5, identical or different, are each H or OH or NH2;
and bond symbol (~) indicates that substituents R3, R4, and R5 may be in an axial or equatorial position, and their pharmaceutically acceptable salts.

2. The compounds of formula (I) and (II) according to claim 1 belonging to the group consisting of:
a) 7-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-.alpha.-L-lyxo-exopyranosyl)-.alpha.-L-lyxo-exopyranosyl] daunorubicinone chlorhydrate;
b) 7-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-.alpha.-L-lyxo-exopyranosyl)-.alpha.-L-arabino-exopyranosyl] daunorubicinone chlorhydrate;
c) 7-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-.alpha.-L-lyxo-exopyranosyl)-.alpha.-L-lyxo-exopyranosyl] doxorubicinone chlorhydrate;
d) 7-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-.alpha.-L-lyxo-exopyranosyl)-.alpha.-L-arabino-exopyranosyl] doxorubicinone chlorhydrate;
e) 7-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-.alpha.-L-lyxo-exopyranosyl)-.alpha.-L-arabino-exopyranosyl]-4-demethoxy-daunorubicinone chlorhydrate;
f) 7-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-.alpha.-L-lyxo-exopyranosyl)-.alpha.-L-lyxo-exopyranosyl]-4-demethoxy-daunorubicinone chlorhyrate;
g) 7-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-.alpha.-L-lyxo-exopyranosyl)-.alpha.-L-lyxo-exopyranosyl]-4-demethoxy-doxorubicinone chlorhydrate;
h) 7-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-.alpha.-L-lyxo-exopyranosyl)-.alpha.-L-arabino-exopyranosyl]-4-demethoxy-doxorubicinone chlorhydrate;
i) 7-0-[2,6-dideoxy-4-0-(2,3,4,6-tetradeoxy-4-amino-.alpha.-L-erythro-exopyranosyl)-.alpha.-L-lyxo-exopyranosyl] daunorubicinone chlorhydrate;
j) 7-0-[2.6-dideoxy-4-0-(2,3,4,6-tetradeoxy-4-amino-.alpha.-L-erythro-exopyranosyl)-.alpha.-L-lyxo-exopyranosyl]-4-demethoxy-daunorubicinone chlorhydrate;
k) 7-0-[2,6-dideoxy-4-0-(2,3,4,6-tetradeoxy-4-amino-.alpha.-L-erythro-exopyranosyl)-.alpha.-L-lyxo-exopyranosyl] doxorubicinone chlorhydrate;
l) 7-0-[2.6-dideoxy-4-0-(2.3,4,6-tetradeoxy-4-amino-.alpha.-L-erythro-exopyranosyl)-.alpha.-L-lyxo-exopyranosyl]-4-demethoxy-doxorubicinone chlorhydrate;

m) 7-0-[2,6-dideoxy-4-0-(2,3,6-trideoxy-3-amino-.alpha.-L-lyxo-exopyranosyl)-.alpha.-L-lyxo-exopyranosyl]-4-demethoxy-8-fluoro-daunorubicinone chlorhydrate;
n) 7-0-[2,6-dideoxy-4-0-(2,3.6-trideoxy-3-amino-.alpha.-L-lyxo-exopyranosyl)-.alpha.-L-lyxo-exopyranosyl]-4-demethoxy-8-fluoro-doxorubicinone chlorhydrate.

3. Process for the preparation of compounds of general formula (I) and (II), respectively where:
R is H or OH or the OR7 group where R7 = CHO or COCH3 or the acylic residue of a carboxylic acid containing up to 6 carbon atoms;
R1 is H or OH or OCH3;
R2 is H or F;
R3 is H or OH;
R4 and R5, identical or different, are each H or OH or NH2;

and bond symbol (~) indicates that substituents R3, R4, and R5 may be either in axial or equatorial position, or their pharmaceutically acceptable salts consisting of the following steps:
i) condensation of a compound of formula (III) where R1 and R2 are as defined above and R6 is H or the OR7 group where R7 is a protective group for an alcoholic function, selected among the acetyl-, dimethylterbutylsilyl- or p-methoxyphenyldiphenylmethyl- groups, with a compound of formula (IV) or (V):
where R8 is H or a protected -OH group; R9 and R10, identical or different, are each H or a protected OH group or a protected NH2 group, and X is a group selected between a halogen or a p-nitrobenzoyloxy group, to give compounds of formula (VI) or (VII):

where R1, R2, R6, R8, R9, R10 and symbol (~) are as defined above;
ii) one or more reactions of removal of the protective groups for OH
and/or NH2 functions from compounds of formula (VI) and (VII) to give compounds of formula (I) and (II), where R, R1, R2, R3, R4, R5 and symbol (~) are as defined above;
iii) conversion, if any, of the compounds of formula (I) and (II) into a pharmaceutically acceptable salt thereof.

4. Process for the preparation of the compounds of formula (I) and (II) according to claim 1, where R1, R2, R3, R4, R5 are as defined above and R
is an OH group, or their pharmaceutically acceptable salts, consisting of the following steps:
i) bromination of the carbon in position 14 of the compounds of formula (I) and (II) or of their pharmaceutically acceptable salts, where R1, R2, R3, R4, R5 and symbol (~) are as defined above and R is H;
ii) hydrolysis of the resulting 14-bromoderivatives to obtain compounds of formula (I) and (II), where R1, R2, R3, R4, R5 are as defined above and R is the OH group.

5. The process according to claim 3 wherein in the compound of formula (IV) or (V) of phase i R8 is H or p-nitrobenzoate, R9 and R10, identical or different, are each H or p-nitrobenzoyl- or an NH2 group protected by a trifluoroacetyl- or allyloxycarbonyl-group.

6. The process according to claim 3 wherein phase i) is carried out in the presence of a condensing agent selected from the group consisting of silver triflate, silver perchlorate, mixtures of mercury oxide and mercury bromide, trimethylsilyltriflate, p-toluenesulphonic acid, trifluoroacetic acid, boron halides, tin tetrachloride, titanium tetrachloride or ion exchange resins, Amberlite R type.

7. The process according to claims 3 and 6 wherein the compound of formula (III) is dissolved in an inert organic solvent and the condensation is carried out in the presence of molecular sieves as dehydrating substances.

8. The process according to claims 6 and 7 wherein the reaction mixture is added during condensation with an organic base selected from the group consisting of pyridine, collidine, N,N-dimethylaminopyridine, triethylamine or 1,8-bis-(dimethylamino) -naphthalene.

9. The process according to claim 3 wherein said halogen in phase i) is chlorine or bromine.

10. The process according to claim 3 wherein in phase ii) a trifluoroacetyl group, which protects a NH2 function, and/or p-nitrobenzoyl- and/or acetyl- groups, which protect OH functions, are removed by the action of an inorganic base selected from the group consisting of sodium, potassium, lithium or barium hydroxide or carbonate.

11. The process according to claim 3 wherein in phase ii) an allyloxycarbonyl group, which protects a NH2 function, is removed by the action of nickel or palladium organic complexes.

12. The process according to claim 3 wherein in phase ii) a methoxyphenyldiphenylmethyl group, which protects an OH function, is removed by the action of an organic acid.

13. The process according to claim 12 wherein the said organic acid is acetic acid.

14. The process according to claim 3 wherein in phase ii) the dimethylterbutylsilyl group, which protects an OH function, is removed in the presence of t e trabutyl ammonium fluoride.

15. The process according to claim 3 wherein in phase iii) the compounds of formula (I) and (II) are converted into pharmaceutically acceptable chlorhydrates.

16. The process according to claim 4 wherein in phase i) bromination is carried out with bromine in chloroform.

17. The process according to claim 4 wherein in phase ii) hydrolysis is carried out with sodium formate.

18. A pharmaceutical composition containing as active ingredient at least a compound according to claims 1 and 2 or a pharmaceutically acceptable salt thereof, combined with a pharmaceutically acceptable carrier or diluent.

19. Use of the compounds according to claims 1 and 2 or of pharmaceutically acceptable salts thereof as anticancer agents for solid tumors or leukemia.

20. Pharmaceutical compositions acting as anticancer agents containing as active ingredient at least a compound according to claims 1 and 2 or pharmaceutically acceptable salts thereof, combined with a pharmaceutically acceptable carrier or diluent.