IE55283B1 - N-(vinblastin-23-oyl)derivatives of amino acids - Google Patents

Abstract

Vinblastine derivatives of the general formula: <IMAGE> wherein R is an ester of an amino-acid which is possibly protected, attached to the vinblastin-23-oyl moiety by an amide bond, the ester group, which may be straight or branched, containing 2-9 carbon atoms and R1 is a hydrogen atom or a hydroxy group, R2 is a hydrogen atom, a formyl group or a C2-C9 acyl group, R5 is a hydrogen atom or a methyl group or a formyl group, with the provision that compounds where R5 is methyl and R1 is a beta -hydroxy group are excluded; or their addition salts with mineral or organic acids. The compounds are useful as drugs. [GB2111055A]

Description

55283 The present invention relates to novel bisindole alkaloids. More particularly, the invention relates to combination products of amino acid with derivatives of vinblastine, to a method for their preparation, their use as antitumoral agents 5 and to pharmaceutical compositions containing same.

These novel derivatives of vinblastine may be used in treating leukemia and malignant tumors in humans.

Bisindole alkaloids of the vinblastine type are well-known compounds having the carbon skeleton of the general formula . . As examples Of these compounds, one-may cite : vincaleukoblastine (U.S. Patent 3,097,137), leurocristine or vincristine and leurosidine (U.S. Patent 3,205,220), vinglycinate (Belgian Patent 659,112) and vindesine (Belgian Patent 813j168). t 2 The latter· compound is obtained by chemical modification of natural vinblastine (I, R^ - OCHg, R2 = COCHg), which is obtainable by extraction from Catharanthus roseus leaves.

Vinblastine, vincristine and vindesine are commercially available for use in human therapy, more particularly for the treatment of leukemia and some solid tumors.

However, these drugs have been shown to possess 10 unfavorable side-effects. Vincristine shows neurotoxie effects and vinblastine , a high toxicity as far as hematopoetic tissues are concerned.

Their mechanism of action is similar to the mechanism 15 which has been postulated for the antimitotic action of colchicine. These drugs would act through inhibition of the polymerisation of tubuline to give microtubules, and subsequent arrest of the cell division in the metaphase.

The utilization of 1:1 complexes of anti-tumoral tubiline- bisindole alkaloids has been described in Belgian Patent 854,053. these complexes exhibit In some cases lower toxicity and more efficient chemotherapeutic activity than the corresponding free alkaloids.

Other chemical modifications of vinblastine have been tested. Thus the vinglycinate sulphate (I, sulphate, Rj = 0CH3; Rj = COCHjN(CHj)2 -Cancer Research 1967, 27, 221-227), has also been tested in clinical experimentation but does not appear 30 generally to be superior to vinblastine or to vincristine. 3 Belgian Patent number 813,168 disclose Vindesine (1,^= NHj, Rj * H) and other vinblastine Cj carboxamide derivatives. Subsequent reports confirmed the therapeutical interest 6f vindesine or 3-carboxamide ^-O-deacetyl vinblastine, but this compound 5 appeared to be inactive for the treatment murine 1210 leukemia inoculated in mice (C.J. Barnett et al., J. Med. Chem. 21, 88, 1978) The new compounds described in the present invention are able to substantially delay the death of mice intravenously 10 inoculated with P 388 and L 1210 leukemias.

Activities on experimental P 388 tumors have appeared, surprizingly, very superior to reference Vinca alkaloids.

Numerous total remissions have been observed.

The compounds of the invention further show other important and unexpected advantages compared to vinblastine and known analogs, especially vindesine.

More particularly, the toxicity which has been observed is generally lower than the corresponding toxicity of vindesine or vincristine.

The new compounds of the present invention are more 25 particularly those of the general formula II : 4 ο wherein R is an ester of an ct-amino-acid which is possibly protected, attached to the vinblastin-23-oyl moiety by an amide bond, the ester group, which is straight or branched, containing 2 to 9 carbon atoms (including that of the carbonyl group) and ^ is a hydrogen atom or a hydroxy group, R? is a hydrogen atom, a formyl group or a Cg to Cg acyl group, Rg is a hydrogen atom or a methyl group or a formyl group, with the proviso that compounds where, Rg is methyl when R1 is β-hydroxy are excluded; or their addition . salts with mineral or organic acids.

The following compounds are particularly preferred: (III) or4 wherein R^ is a hydroxy group or a hydrogen atom, R2 is a hydrogen atom, a formyl group or a C2~Cg acyl group, R3 is a hydrogen atom, straight or branched C^-Cg alkyl, hydroxy-C^-Cg-alkyl, aminohydroxy-C^-Cg-alkyl, carboxy-C^-Cg-alkyl, guanidino-C^-Cg- alkyl, amino-C^-Cg-alkyl, thiol-Cj-Cg-alkyl, cysteinyl-methyl, methylthio-ethyl, benzyl, hydroxy-benzyl, or a group : or R3 together with the carbon to which it is attached and the nitrogen of the amido-group, forms pyrrolidine or an hydroxy-pyrrolidine ring; Rg is a hydrogen atom or a methyl group or a formyl group and R4 is a straight or branched C^-Cg-alkyl, 6 with the proviso that compounds where simultaneously r is β - OH and Rj is -CH3 are excluded; or their addition salts with a mineral or organic acid. The group -COOR^ is preferably the carboethoxy or the carbomethoxy group.

In a preferred embodiment, the structural segment R, 0 |3 II -NH-CH-CORjj in general formula III, represents an ester derived from any of the naturally-occuring amino acids and their optical isomers of D-configuration, namely glycine, alanine, valine, leucine, isoleucine, serine, threonine, aspartic acid, glutamic acid, aspargine, glutamine,arginine, lysine, cysteine, cystine, methionine, phenylalanine, tyrosine, tryptophane,proline, histidine hydroxy-lysine or hydroxy-proline.

The compounds may be designated as 3-decarbomethoxy-4(0)-deacetyl vinblastine-3-carboxamide. They will however be preferably designated as N-(vinblastin-23-oyl) or N-(vincristin-23-oyl) derivatives of amino-acids hereafter.

Particularly preferred compounds of the invention of general formula II are those wherein R2 is hydrogen and the amino acid moieties are derived from one of the following amino-acids : L or D tryptophan, leucine, isoleucine, valine, alanine or phenylalanine. Among these, L-tryptophane,L-isoleucine and L-alanine are particularly interesting. 7 The present invention describes more particularly reaction products of amino-acids with vincristine, 4(0)-deacetyl vincristine, N-deformyl-4(0)-deacetyl vincristine and deoxy-vinblastine.

The latter compound may be obtained by hydrogenation of 5 anhydrovinblastine obtained by dehydration of vinblastine or by coupling vindoline with catharantine (Potier et al, 3ACS 98 7017, (1976)).

The invention provides particularly: Ethyl or methyl N-4(0)-deacetyl-vincristin-23-oyl) tryptophanate; Ethyl or methyl N-4(0)-deacetyl-N-deformyl-vincristin-23-oyl) 10 tryptophanate; or Ethyl N-4(0)-deacetyl-deoxyvinblastin-23-oyl-B) tryptophanate; or an addition salt of any of these with a pharmaceutically acceptable acid.

The most preferred compound of the invention is ethyl N-4(0)-deacetyl-4‘-deoxyvinblastin-23-oyl-B) tryptophanate.

When the amino acid contains functional groups in the side chain R3 (formula III) such as lysine or cysteine it may be necessary to protect the functional groups according to methods well known to those skilled in the art.

Protection may be achieved, depending on the nature of the group to 20 be protected by condensing a benzyl, t-butyl, benzyloxycarbonyl, t-butoxy-trifluoroacetyl carbonyl or trityl radical. Other well known protecting groups in use in peptide chemistry may successfully be used.

The compounds of the present invention may be prepared in the conventional manner starting from corresponding derivatives of 25 vinblastine, by hydrazinolysis followed by nitrosation and reaction with the amino acid ester in accordance with the reaction sequence I:- 8.

Reaction sequence I The first step of the process is to add anhydrous hydrazine in excess to a solution of vinblastine base in anhydrous methanol. The solution is heated in an inert atmosphere for 12 hours to 12 days at a temperature between 30°C and 70°C.

Most preferably the temperature is maintained around 60eC.

The hydrazide of the bis-indole derivative is then isolated by adding water, extracting with dichloromethane and concentrating. The compound may be later purified by preparative 25 chromatography (neutral silica). In the case of vincristine, the product obtained is the 4(0)-deacetyl-N -deformyl -vincristine carbo-xhydrazide. 9 During the second step, the hydrazide function of the modified vinblastine is transformed into an acyl azide. This transformation is achieved in a known manner by adding sodium nitrite to the hydrazide dissolved in a water-methanol-5 acidic mixture.

The acid which is used may be hydrochloric acid.

The reaction temperature is maintained between 0SC 10 and 5eC. After extraction with a water-immiscible aprotic solvent, preferably methylene chloride, the organic phase is partially concentrated.

The acyl azide proper is preferably not isolated but 15 directly added to the amino acid ester or possibly a protected derivative thereof, dissolved in methylene chloride.

The quantity of amino acid, to be used is about one to five equivalents of the modified vinblastine carboxazide.

The reaction mixture is maintained between -3eC and +10ec for 8-72 hours and generally for about 15 hours. Monitoring of the reaction is easily achieved by thin layer chromatography. After concentrating, the compound of the 25 invention of formula II may be transformed into a sulphate salt or another salt derived from a mineral or organic acid, by crystallization from a methanolic solution of the corresponding acid.

The compounds of the invention may be purified by 30 conventional techniques of chromatography and re-crystallization.

If desired, the thus obtained 4(0)-deacetyl vinblastine derivative can be reacylated either directly to give the vinblastine derivative χχχ wherein Rj is COCH3 (J.Med.Chem.22, 391, 1979) or through the preliminary formation of the 3,4-5 diacetoxy derivative followed by a selective hydrolysis of the 3-acetoxy group in the position 3. The hydroxy group in may be, in a conventional manner, esterified by other activated acid derivatives containing 2-9 C atoms. The 0-4 formyl derivatives are obtained by formylation (formic acid-10 acetic anhydride) of the corresponding 4(0 )-deacetyl compounds (see Belgian Patent 660,843).

The present invention relates also to the industrial and particularly pharmaceutical applications of the new 15 bisindole alkaloids.

The compounds of this invention display particularly very useful antitumor properties which may be applied in human therapy.

These amino-acid derivatives may be used for the treatment of L 1210, P 388 type leukemia, gliomas, lymphosarcomas and other leukemias or malignant tumors. In human medicine they are used for the treatment of Hodgkin's disease and for other 25 solid tumors treatable with vinblastine, vincristine or vindesine. These compounds are also useful in veterinary medicine for the treatment of tumors of the animals.

Other interesting therapeutical uses may also be contemplated for the new derivatives of bisindole alkaloids. It has been described that vinblastine may be used for treating some 11 30 t - forms of arthritis (U.S. Patent 4,208,411) and that vincristine may be used for treating psoriasis (U.S. Patent 3,749,784).

For their therapeutical use, the compounds of the invention, possibly in the lyophilized form, are preferably 5 administred by parenteral route, dissolved in a pharmaceutically acceptable solvent, in the form of a base or of a pharmaceutically acceptable acid addition salt. Among the acid addition salts, the non-toxic and pharmaceutically acceptable salts, such as inorganic acid salts as hydrochloric acid, phosphoric acid and 10 sulfuric acid salts or organic acid salts as acetic, propionic, succinic, tartaric, oxalic, methanesulfonic and benzene-sulfonic acid salts are preferred. The 1:1 addition salts with sulphuric acid are of particular interest.

Physiological water and other saline solutions which 15 have been buffered, for instance with a phosphate are appropriate solvents. In general, the compounds Can be used in human therapy in an analogous manner to the technique and limitations in use for other alkaloids of the Vinca type.

The active substance is generally distributed at a posology varying between 0.01 mg to 5 mg/kg depending upon the derivative and the therapeutic schedule whis is adopted.

Total weekly doses will vary generally between 0.1 and 35 mg/kg.

The composition in accordance with the invention are prepared as unitary doses of 2 to 900 mg. 12 The compounds of the invention may be used alone or in combination with other carcinostatic agents including, for example, the alkylating agents, the anti-metabolites such as methotrexate, 5-fluoro-uracil, 6-mercaptopurine, 6-thioguanine, 5 the cystosine arabinosides, and antibiotics such as actinomycine D, daunorubicine, adriamycine and cis-diamino-dichloro-platinum. In particular, the new vinblastine derivatives may be used in combination.

The following specific examples illustrate in a non- limitative way the process for obtaining the compounds of the invention.

Example 1 15 1. Preparation of 4(0)-deacetyl-N-deformyl-vincristine monohydrazide A. 985 mg of vincristine base are dissolved in a mixture of 10 ml anhydrous hydrazine and 10 ml methanol. The reaction mixture is maintained at 60 * C, while stirring, for 22 hours.

The reaction mixture is then treated with water and thereafter with water saturated by NaCl. The aqueous solution is extracted 8 times with 15 ml dichloromSthane. The collected organic phases are treated with 20 ml water, thereafter 25 ml water saturated by NaCl and finally dried on 25 Na2 S04· After filtration and vacuum concentration, 900 mg of O-4-deacetyl vincristine monohydrazide (purity over 90%) have been obtained. 13 NMR spectrum (0001^,3 60 MHz) 9.76 (s,lH), 8.37 (s,lH), 8.06 (s,lH), 7.53 (d,lH) , 7.24 and 7.07 (m,3H)r 6.82 (s,lH), 6.22 (s,l), 5.87 (dd,lh), 5 5-67 (d,lH), 5.43 (s,lH, 4.03 (s,lH), 3.94 (s,3K), 3.86 (s,lH), 3.73 (s,3H), 3.52 (s,3H), 2.82 (s,2H), 2.51 (s,lH), 0.93 {2t, 2 x 311) Mass Spectrum (electronic ionisation impact) 10 154, 294, 355, 413, 524, 555, 695, 710, 723, 736, 739, 755 (M + 1) > 768, 769, 782 calculated for C42H54N6°7 ^54,942 2. Preparation of acid azide of modified vincristine 15 A solution of 850 mg of vincristine monohydrazide A in 20 ml methanol is treated with 63 ml HC1 1 N and 175.5 mg sodium nitrite for 15 minutes at 0eC.

The solution maintained at 0eC is then neutralised by NaHCO^ at 0eC and thereafter extracted 3 times with dichloromethane. 20 The collected organic phases are dried on Na2SC>4, filtered and vacuum concentrated without heating until a solution of about 10 ml is obtained. 3. Reaction with ethyl tryptophanate 25 300 mg of ethyl tryptophanate are then added while stirring at about 4eC and the reaction is checked by tic. After 10 days, the reaction product is purified by chromatographic separation (40 g silicagel 60, elution solvent ether /NII^ 14 saturated methanol 96:4 volume/volume). Fractions of 15 ml are collected which are checked by tic. The non-reacted amino-acid is first collected (fraction 30 to 40). The elution agent is changed (ether/NH^ saturated methanol 86:14) 5 and the reacted derivatives are collected as three fractions: fractions 44 and 45:30 mg ; fractions 46 - 53:257 mg ; fraction 54 - 60:115 mg).

The second part was ethyl N-^(O) -deacetyl-ttdeformyl vincristin-23-oyl) tryptophanate la which was homogeneous by tic.

Mass spectrum : 984, 970, 956 (M+ + 1) 913, 912, 899 (DCJ isobutane), calculated for ^55 Hgg Nfg 0g : 955.,181.

UV spectrum (CH30H) : 15 max : 282 (4,20) , 290 (4,18), 322 (3,96)nm min : 254, 287, 305 nm IR spectrum : (cm-1) 3400 - 2920 - 1720 - 1660 - 1610 - 1485 - 1450 - 1370 - 1345 20 1330 - 1290 - 1220 - 1165- 1130 - 1025 - 1005 - 920 - 885 830 - 740 NMR Spectrum (CDC13) 360 MHZ (ppm) 8.50 (s, 1H) 25 8.03 (s, 2H) 7.77 (d, 1H) 7.60 (d, 1H) 7.57 (d, 1H) 6.95 (s, 1H) 15 6.35 (s, III) 5.89 (d.d., 1H) 5. 78 (d, 111) 4.75 (q, 1H) 5 3. 88 (s, 3II) 3.67 (s, 311) 1.23 (t, 3H) 0. 98 (t, 3H) 0. 89 (t, 3H) 10 Ethyl N-4(0) -deacetyl vincristine-23-oyl) tryptophanate IB.

The deformylated derivative I a (257 mg) is re-formylated by applying the method described in Belgian Patent 811,110 15 The raw product thus obtained is purified by chromatographic separation using a 20 cm column (silicagel, 30 g) and succesi-vely 3 elution agents : ether/NH^ saturated MeOH 92:8 ; 88 : 12, 36 : 14. The eluent is collected as 15 ml fractions. The fractions 44 - 54 (34.1 mg) contained the N-reformylated 20 derivative lb.

Mass spectrum (isobutane OCX) : 1011,997, 983 (M+ +1), 970, 982, 996, 998, 999, 1012 calculated for C5gH66N6010 = 983*192 25 UV spectrum (CH^OH) (nm) max : 270 (4 .18) 290 (4.11) plateau (4.12) shoulder (4.03) 16 IR spectrum (KBr) (cm 1) bands at 3400 - 3040 - 2960 - 2920 - 2880 - 2850 - 1735 -1725 - 1680 - 1670 - 1665 - 1610 - 1490 - 1450 - 1225 - 745.

Example 2 Ethyl N - 4(0)-deacety1-4'-deoxy ~ vinblastine - 23 - oyl -B) tryphtophanate Ic.

The 4(-0)-deacety1-4'-deoxy-vinblastine hydrazide is prepared by 10 the method described in U.S. Patent 4,203,898 (assigned to Ely Lilly Co., column 24, line 51 and following). 500 mg of the hydrazide in 12 ml methanol are thereafter treated with 37 ml HC1 IN and 104 mg NaNO^ for 15 minutes at OeC.

The solution is thereafter neutralized by NaHCOj and extracted six times with 15 ml dichloromethane. The organic phases are dried on Na-SO, and concentrated until a volume of about 10 nl 2 4 is obtained.

The azide in solution is then brought into contact with ethyl tryptophanate (300 mg) at 4°C while stirring. The reaction is checked by tic (ether, MeOII). After 6 days, the reaction is completed and the reaction product is purified by column 25 chromatography on silicagel (18 cm, 30 g), elution by 15 ml fractions. 17 The following elution agents have been successively used : Ether 96 NH3 sat, MeOH 4 fractions 1-49 92 8 fractions 50-57 86 14 fractions 71-90 5 The fractions 50-57 contain the wanted reaction product Ic (108 mg).

The sulphate is prepared by ether precipitation (2 % H2S04/ 10 ethanol).

UV spectrum of Sulphate (CHjOH) (nm) max : 224 (4 .63) , 272 (4.32) min : 247 (4 .03) 15 shoulder : 286 (4.22) - 312 (3. 72) IR spectrum (KBr) of Sulphate 3420 - 3060 - 2960 - 2930 - 2880 - 2600 (weak ) - 1725 1660 - 1615 - 1500 - 1455 - 1430 r 1375 - 1230 - 1105 - 20 1060 - 1015 - 920 - 745 cm-1.

NMR spectrum (CDCl^) 360 MHz of the base in ppm. 9.46 Ξ 1 H 7.53 d 1 H 4.94 q 1H 8.34 S 1 H 7.30 d 1 H 4.18 d 1H 25 7.92 S 1 H 6.51 s 1 H 4. 05 q 2H 7. 67 d 1 H 6.04 s 1 H 3. 77 S 3H 7.59 d 1 H m. about s. centered on 5.81 18 3.58 S RH 3.47 s 1H 2.82 s 2H 2.77 s 3H 2-59 s 1H 1.14 t 3H 0-95 t 3H 0-87 t 3H Mass spectrum of the base DCI isobutane M + 1 + at 954 M + 14 + l+at 968 M + 28 + 1+ at 982 ions at 153 - 155 - 157 - 171 - 172 - 185 - 186 -199 213 - 223 - 227 - 255 - 257 - 279 - 281 - 283 285 - 349 - 398 - 459 - 516 - 569 - 952 - 953 955 - 967 - 969 - 981 - 983 calculated for ' C56 H68 N6 °8 5 953,208 19 Bxanple 3 Ethyl N (4(0 )-deacetyl-41-deoxy-yinblastin-23-oyl-B)-isoleucinate.

A solution of 4(0)-deacetyl-4'-deoxyvinblastine -B 5 hydrazide (0.6g, 0.79 mM-see US patent 4 203 898 column 24 line 51) in a mixture of 15 ml CH^OH and 45 ml HC1 1 N was cooled to -7°C. NaNOj was added to the solution (0.15 g) and stirring was continued for 13 minutes at -7eC. After addition of an aqueous saturated solution of NaHCOj till a pH-value 10 of 9 is obtained, the resulting solution is extracted four times with Ci^Clj- The combined organic phases were washed with sat.aqueous NaCl solution and dried over MgS04.

The solution was concentrated to a volume of 15 ml 15 and ethyl isoleucinate (1.25 mM) was added. The reaction mixture was allowed to stand 4 days in a refrigerator. The solvent was the evaporated under reduced pressure. The residue was purified by column chromatography (Si02, 60g) and eluted with ether/CH^OH/NHg (96:4).0.25 g of amorphous 20 product (yield 35 %) have been thus obtained.

Mass .spectrum s (Molec.Ionisation isobutane) 880(M+), 894, 836, 849, 832, 445; 391, 355 cm-1 C51H69N5°8 = β80·1 25 Melting point 18o-190°C aD = 104° (0=0.154) IR (CHC13) 3470, 2970,1728, 1655, 1612, 1502 cm"1 UV (CH30H) 289, 268, 216 nm 20 NMR (CDC13) 7.9(NH), 654 and 6.06 Hg, H12, 5,81 4.60 (CHC02(NH)) 3.76 C02CH3 , 3.58 CHj-O , 3.33 and 2.85 (H3A and H3B) , 2.73 (N-CH3> , 0.69 (H-15').

Acute toxicity-Determlnation of LD,.q The acute toxicity of the compound of Example 2 s ethyl N - (4(0) - deacetyl - 4' - deoxy - vinblastine - 23 - oyl - B) tryphtophanate has been determined on female NMRI mice.

Increasing doses of the drug have been inoculated intravenously 10 in a single injection. The mortality percentage is determined as a function of the time. The LD^q values for the above compound (deoxy VTrpE) and a reference product : deoxy-vinblastine (deoxy VliL) are indicated hereafter Drug o in Q >1 15 Deoxy VBL 20 Deoxy VTrpE 91.5 (i.e.Compound Ic) The compound deoxy VTrpE is thus less toxic than the reference compound.

Antitumoral activity The chemotherapeutic activity of the sulfate salt of deoxy VRrpE has been studied on the lymphoblastic leukemia L 1210 and P 388. 1 L 1210 A Female DBA2 mice have been inoculated by lO leukemic cells. The product is administrated by intravenous route, the day after the graft at a 50mg/kg dose. The mortality of the animals is observed as a function of time. Table I hereafter 21 indicates the results obtained with the compound of Example 2 (Ic). At the tested dose, the compound is more active than vinblastine. This superiority has been confirmed compared to deoxy-vinblastine. 2. P388 Female DBA2 mice are intravenously inoculated by 4 10 leukemic cells. The products are i.v. administrated, the day after the graft. The mortality of the animals is observed as a function of time. Results appear in Table I.

Deoxy VTrpE is clearly more active than the reference compound and indicates a higher percentage of surviving subjects at long term. 22 (Λ ΑΧ Ο Φ «W XX 030 ta ko Φ ‘ r· 0' >1 id C <0 +J Ή ro c > 0) ·Η -M 0 > « P P Φ 3 CU ·« Uh0 -P Φ (d onj c cn ro 4_J-H -P C > 0 >1 Q}*H O id ϋ > ·ηΌ P P XX 11)33 a, ia w (0 XX dP H W >1 a co *0 S'. o ro to P r—1 Φ td XX w e £ 0-H 0 c z < ro O O O O O 0 O O o o O m ro Ο O m r» vo σ\ o r- r- ο O\o co co * σ» U 4J W rH £3 r+ β TJ«3 a)P td M σ»3P Q) Λ E* 0) 0 UJ CN Γ"» 00 pH H cn CN ϋ •H in •«1· in Λ σ* H r-1 pH iH CN CN d Φ CO CN VO 00 in o in •H m in VO o O O O H H H pH ro co ro ro o o o pH pH H in in 00 σ» O 00 O O O in in ro 'a· in m XX w Q, Hi w ax » M m ffl a > > £t > > u > E-« O H 00 CN 00 pH ro XX & Io >1XI φ -μ 00 p > H >1 c XX * (0 ρ e •H cd (fl -H > Φ U u a) jj 0 ϋ ο φ U) c •H iH 6 ® c -P fd UH CNd •p| 0 < o V CQ P 0) 4P a £ II 11 pH · <*> fd Ή s CO 1 CO XX 2 M 23 The acyl group which can represent is preferably an alkanoyl group.

The present compounds are particularly useful for treating neoplastic diseases. 24

Claims (5)

1. A compound which is a vinblastine of general formula: or a salt thereof, wherein 5. represents an ester of an optionally protected α-amino-acid, which ester is linked via the a nitrogen atom and the alcohol part of the ester being straight or branched and containing 1-8 carbon atoms; Rj represents a hydrogen atom or a hydroxy group; R2 represents a hydrogen atom, a formyl group or a C2~C9 acyl 10 group; and R5 represents a hydrogen atom or a methyl group or a formyl group; with the proviso that Rs does not represent methyl while Rj represents β-hydroxy.

2. A compound according to claim 1 which is a vinblastine of general 15 formula: 25. or a salt thereof, wherein Rt represents a hydroxy group or a hydrogen atom; R2 represents a hydrogen atom, a formyl group or a C2-C9 acyl 5 group; R3 represents a hydrogen atom, straight or branched i^-Cg alkyl, hydroxy-CL-Ca-alkyl, hydroxyamino-C,-Ca-alkyl, carboxy-Cj-C8-alkyl, guanidino-Cj-C,, -alkyl, amino-f^-Cg-alkyl, 10 thiol-C1-C8-alkyl, cysteinyl-methyl, methylthioethyl, benzyl, hydroxybenzyl, or a group; or R3 together with the carbon to which it is attached and the nitrogen of the amido group represents a pyrrolidine or an hydroxy-pyrrolidine ring; 15 Rs represents a hydrogen atom or a methyl ijroup or a formyl group; and 26. R, represents a straight or branched Cj-C8-alkyl group; with the proviso that Rs does not represent methyl while Rt represents g-hydroxy.

3. A compound according to claim 1 or 2 which is an addition salt of the vinblastine with a mineral or organic acid.

4. A compound according to claim 1 wherein the vinblastine is specifically named herein. 5. Ethyl N-(4(0)-deacetyl-vincristin-23-oyl) . tryptophanate or an addition salt thereof with a pharmaceutically acceptable acid. 6. Ethyl N-(4(0)-deacetyl-N-deformy1-v i ncri st i n-23-oy1) tryptophanate or an addition salt thereof with a pharmaceutically acceptable acid. 7. Ethyl N-(4(0)-deacetyl-4'-deoxyvinblastin-23-oyl-e) tryptophanate or an addition salt thereof with a pharmaceutically acceptable acid. 8. A compound according to any one of the preceding claims wherein the addition salt is the 1:1 addition salt with sulphuric acid. 9. A compound according to claim 1, which compound is substantially as described herein. according to any of preceding claims 5 to 7, 10. A compound which is a vinblastine derivative or a salt thereof^, which derivataive or salt thereof is substantially as described herein in any one of the Examples. 11. Pharmaceutical composition for use in human or veterinary medicine, which composition comprises a pharmaceutically acceptable carrier and one or more vinblastines or pharmaceutically acceptable salts thereof, which vinblastines and salts thereof are as claimed in any one of the preceding claims. 27. 12. Composition according to claim 11 in unit dosage form, the unit dose containing 2-900 mg active compound. 13. Composition according to claim 11 or 12 containing as active compound ethyl N-(4(0)-deacetyl-vincnstin-23-oyl) tryptophanate or an addition salt thereof with a pharmaceutically acceptable acid. 14. Composition according to claim 11 or 12 containing as active compound ethyl N-(4(0)-deacetyl-N-deformyl-vincristin-23-oyl) tryptophanate or an addition salt thereof with a pharmaceutically acceptable acid. 15. Composition according to claim 11 or 12 containing as active compound ethyl N-(4(0)-deacetyl-4'-deoxyvinblastin-23-oyl-B) tryptophanate or an addition salt thereof with a pharmaceutically acceptable acid. 15. Composition according to claim 11 substantially as described herein. 17. A compound for use in a method of treatment or the human or animal body by therapy, which compound is a vinblastine or a pharmaceutically acceptable salt thereof, which vinblastine or salt thereof is as claimed in any one of claims 1 to 10. 18. A process for the preparation of a compound claimed in any one of claims 1 to 10, which process is substantially as described herein. 19. A process for the preparation of a compound claimed in any one of claims 1 to 3, which process is substantially as described herein in any one of the Examples. Dated this 7th day of December 1982 TOMKINS & CO.

5. Dartmouth Road, DUBLIN 6 (signed) Reference has been directed in pursuance of Subsection (1) of Section 14 of the Patents Act, 1964 to patent no. 42385.