CS235979B2 - Method of new anti-tumor analogues-daunorubicine and doxorubicine production - Google Patents

Abstract

<IMAGE> The anthracycline glycosides I (X = H or OH, R1 = H or CH3, R2 = H or OCH3, R3 = H or OCH3, R2 = R3) and their pharmaceutically acceptable acid addition salts have antitumour properties. They are prepared from 4-demothoxy-daunomycinone or 2,3-dimethyl-4-methoxy-daunomycinone by condensation with an appropriate N-protected hexopyranosyl chloride and removal of the protecting group and, in the case X = OH, conversion of the 9-acetyl group to a 9-hydroxyacetyl group.

Description

The present invention relates to novel anti-tumor analogues of daunorubicin and doxorubicin of formula I

where

X is a hydrogen atom or a hydroxyl group,

R 1 is a hydrogen atom or a methyl group, one of R 8 and R 6 is a methoxy group and the other of R 8 and R 8 is a hydrogen atom, and their pharmaceutically acceptable acid addition salts.

4-desmethoxy-4-O-methyl-daunorubicin (Ia: R = = X = H, ⁼ OCH 3),

These are the following compounds:

4-desmethoxy-4'-epi-4'-O-methyl-daunorubicin (Ib: R 6 = R 8 = X = H, R 3)

OCHp phi ₃ = X = H), = and ₃ ),

4-desmethoxy-4-O-methyl-doxorubicin (Ie: R = R = H, R ₂ = OCH _3, X = OH)

4-desmethoxy-4'-epi-4'-O-methyl-doxorubicin (If: R 1 = R ₂ = H, R ₃ = OCH _3> X = OH),

4-desmethoxy-2,3-dimethyl-4'-O-methyl-doxorubicin (Ig: R Ig = CHj, Rg = OCH ^, R ₃ = H, X = OH), and

4-desmethoxy-2,3-dimethyl-4'-epi-4'-O-methyldoxarubicin (1h: R 1 = OH).

ch ₃ , r ₂ = H, r ₃ = and ₃ ,

The process according to the invention for preparing dauhorubicin and doxorubicin analogues according to the invention is characterized in that the 4-demethoxy-daunomycinone or 2,3-dimethyl-4-demethoxy-danoniycinone dissolved in anhydrous methylene dichloride is reacted at room temperature with 2, 3,6-trideoxy-3-trifluoroacetamido-4-O-methyl-L-lyxo-hexopyranosyl chloride or 2,3,6-trideoxy-3-trifluoroacetamido-4-O-methyl-L-arabinohexopyran * oxyl chloride in the presence of trifluoromethanesulfonate silver and molecular sieves to form the appropriate N-trifluoromethyl-protected alpha-glycosides, removing the N-trifluoroacetyl protecting group by mild alkaline hydrolysis with 0.2N aqueous sodium hydroxide, and forming the corresponding daunorublcin derivatives (I: X = H), optionally converting them to the corresponding doxorubicin derivatives (I: X = OH) by bromination and treatment of the thus formed 14- · bromo-intermediate compounds with formene sodium.

The invention is illustrated by the following examples and biological data.

Example 1

4-Desmethoxy-4 * -O-methyldaunorubicin <(Ia)

A solution of 3.68 g of 4-desmethoxydaunomycinone in 400 ml of anhydrous methylene chloride containing 1.4 g of 1-chloro-4-O-methyl-N-trifluoroacetyldaunosamine was vigorously stirred in the presence of a molecular sieve (30.0 g, 4 Merck) and 1.3 g of silver trifluoromethanesulfonic acid salt. After 10 minutes at room temperature, the reaction mixture was neutralized with 0.55 ml of symidine. After 40 minutes the suspension was filtered and the organic phase was washed with 0.01 N aqueous hydrochloric acid solution, water, saturated aqueous sodium bicarbonate solution and finally water until neutral. The residue obtained by evaporating the solvent in vacuo was dissolved in 150 ml of acetone, treated with 600 ml of aqueous sodium hydroxide solution and diluted with 450 ml of water. After 5 hours at 0 ° C, the pH of the solution was adjusted to 8.5 and the solution extracted with chloroform until the chloroform solutions were colorless. The organic extracts were combined and acidified to pH

0.1N methanolic hydrogen chloride. Concentration in vacuo to a small volume (150 mL) yielded 0.6 g of pure 4-desmethoxy-4'-O-methyldaunorublcine. The mother liquor was purified on a column of silica gel buffered to pH 7 with phosphate buffer M / 15 using a chloroform: methanol: water (10: 2: 0.2 by volume) solvent system. The eluate containing the pure material was diluted with water and the organic phase was separated, washed with water and evaporated to a small volume and then acidified to pH 5 with 0.1N methanolic hydrogen chloride. An additional 0.4 g of 4-desmide hydrochloride was obtained. 189 DEG-190 DEG C. (with decomposition). Melting point: 189 DEG-190 DEG C. (with decomposition). with silica gel (Merek F 254), chloroform: methanol: water solvent system (10: 2: 0.2 v / v).

High Pressure Liquid Chromatography: Ex [α] ω (1 μm): Analysis: microbondapack column C 18, urine phase: platoon: acetoottoil (69:31 v / v) at pH 2 with 10% reflux acid ratio 1.5 ml / min, holding time 22 min.

FD-MS: m / z 511 (M ^& lt ^{; +} & gt ^; )

Example 2

4-Desmethoxy-4 * - O-mathohl-doxooubicin (Ie)

A solution of 0.5 g of 4-desm-thiophene prepared as described in of Example 1, in a mixture of 8 mL of methanol and 20 mL of dioxane, was reacted with bromine to give the 14-bromo derivative The reaction of the 14-bromo derivative with an aqueous sodium formate solution at room temperature for 18 hours afforded 0.310 g of 4-desaetho. 164 DEG-165 DEG C. (decomposition), tetOorrsOpened silica gel plate chromatography (Merek F 25-4), solvent system chlorototot thanol: water (10: 2: 0.2 by volume, Rf 0.18.

Pressure liquid chrtaakokrrk‘ie: experimental conditions: mícrkbondopkck. . mobile phase: rota: akettotttil (6931 v / v) at pH 2 with 10% acetic acid, reflux ratio 1.5 ml / min, holding time 10 min. '

Example 1 a d 3 »

4-desaeetlOkyt-, 2-dimethhtL4 * -O-aethtldaunooubbcin (Ic)

The co-initiation reaction between 4-desaethoxy-2,3-damerydalluoroacetic acid and 1-chloro-4-methyl-N-trifluoroacetyllactocyanate under the conditions described in Example 1 gave the title compound.

Př.íílaaá.

4-desaquino- _J 3-dimethyl-4 * -0-aethtldoxorubicit (Ig)

The conversion of compound Ic to the title compound was. was performed using the method described in Example 2.

Example 5

4-desmethoxyt4'-ei-4'-O-aethtldkunorubicin (Ib) and 4-desaetyl2,3-dimeth0ht-4 * -diaethУl-4'-epi-4 * -0-aethtt-dkunorubbitite (Id)

The co-coupling reaction of 4-desaethoxydicyclocincinone and 4-desaethoxt-2,3-dialethyldifluoroacetin with 2,3,6-triestyl-4'-ethyl-triethylcetyl-4-a-ethyl-1H-araticoeek, as described in the example, exemplified by the example described in the example below. after hydrolysis of the N-protecting groups to the tHu compound.

Example ^ d 6

4-063 ^^ 007-4, - ^ 1-4 ^ 0- ^ 11 ^ / 10 (^ 001 ^) 1 (21 ^ (1f) and 4-methoxy-2,3-dimethyl-4'-epi -4'-O-methyldoxorubicin (Ih) t Compounds Ib and Id were converted via their 4-bromo derivative under the conditions described in Example 2 to compounds If and Ih.

Biological activity of Ia and Ie

Compounds Ia and Ie were tested in comparison to the starting materials and the starting compounds. with daunoouUicin (DNR) and doxorubicinee (DX), in various experimental systems to determine their cytotoxicity, anti-tumor efficacy and cardiac toxicity in experimental animals.

The data presented in Table 1 show that Ia is 5 times cytotoxic than the DNR and Ie is about 9 times cytotoxic than DX.

The primary in vivo screening was. was performed on ODF-1 mm ^ with P388 ascitic leukemia (10 6 cells / mmy). The results are shown in Table 2.

Ia and Ie have been found to be more toxic and more potent than the starting compounds. Comparison of the tolerated doses (MyTD) shows that Ia is effective as DNR (results in a similar increase in mouse survival) and has good anti-tumor efficacy) whose size is in the same order of magnitude as DX.

Several studies have been performed in C3H mice with Gross leukemia after iv injection ⁽² x ¹⁰ 0 b / v). Data on ^I and are given in • wand ³ . Filed in the en ^d day after tumor inoculation, substance Ia was clearly less toxic and more effective than DNR. A P4 MyTD of 1.25 to 1.3 m 2 / kg was more effective than the DX at a MyTD of 10 m / kg. It is well known that DNR is ineffective at oral administration at very high doses (> 50 m / kg). The data presented in Table 3 show that Ia has good antitumor activity against Gross Leukemia even when administered orally. After oral administration for only 1 day, Ia is effective at a dose of 1.25 to 1.3 mg / kg, which is also the optimal dose for iv treatment. The results do not indicate that absorption of Ia by the gastrointestinal trake is very effective. After oral administration on Day 1, 2, and Day 3, Ia is more effective than when given only for one day; at an optimum dose of 0.66 m / kg / day, it has an antitumor size of the same order of magnitude as 4-ethoxyethoxy which was followed in parallel at an optimum dose of 1.9 mmgkg / day. The observation that the optimum dose of Ia is lower than that of the 4-thyununicin suggests more effective absorption by the gastrointestinal tract, also compared to this compound.

Data on the antitumor efficacy of Ie compared to DX against Gross Leukemia are shown in Table 4. Compounds were administered one day after tumor cell inoculum; DX was administered i.v .; Ie was administered i.v. and orally. Po · i.v. administration at a MyTD of 1 mm / kg, Ie showed good anti-tumor efficacy, similar to that seen after treatment with DX. In addition, Ib was also effective after oral administration at doses of 1.3 mg / kg.

Ie was tested against L1 210 leukemia, which was vaccinated i.p. to mice · CDF-1 (ascites form) or i.v. (10 · cells / ey-). Treatment was performed one day after inoculation with tumor cells, i.p. or i.v. The DUa shown in Table 5 show that in i.p. - i.p. The Ie at MxTD 0.83 mg / kg corresponded to the DX efficacy at MxTD 4.4 vд / kg. In an i.v.-i.v.

Even at tolerated doses of 1 and 1.3 in / kg, the pgstinadsrssu was superior to DX.

In order to assess the efficacy of the solid tumor, it was tested in comparison with DX against the carcinoma of the mammary gland of mm3 female C3H. A third generation tumor transplant was used. Treatment started 15 days after tumor transplantation and was performed i.v.

once a week for 4 weeks. Tumor measurements were performed with a tapper every week. Tumor-free was treated in parallel to assess general toxicity and cardiac toxicity, which were followed in 5 mice treated with the highest doses of both compounds and sacrificed 5 weeks after the last treatments. The results of this treatment are shown in Table 6. DX was very effective and inhibited growth by 93-94% (compared to untreated controls) at both doses tested (6 and 7.5 m / kg). In tumor-free mice treated with DX at a dose

7.5 m / kg, toxic deaths were observed (2/3) and all myocytes examined showed histologically detectable cardiac damage. le at a dose of 0.4 mg / kg bolle, moderately effective; at doses of 0.6 and 0.75 mm / kg, mpg5 was effective; at 0.6 and 0.75 mg / kg, it clearly inhibited tumor growth. No atrium lesions were observed in tumor-free mice treated with Ie at 0.75 mg / kg and only 2 out of 5 mice had observable ventricular lesions that were less severe than those observed after DX treatment.

The data presented herein show that Ia and Ie are novel, anthrole and cyclic analogs with very interesting biological properties. Compared to JJRD, la is about three times more effective after i.p. administration and about 8 times more effective after i.v. administration. For example, MxTD has antitumor activity against ascites P388 and systemic Gross leukemia equivalent to D.IR. In addition, it is also effective after oral administration, particularly when the treatment is carried out for three consecutive days at lower doses than 4-desethoxydicyclootine.

Ia is about 10 times more potent in vivo than DX. Comparison with MxTD shows with respect to DX that it is equally active against P388 ascites and leukemia. L 1 210, systemic Gross leukemia and solid mammary carcinoma, and is more effective than DX in the treatment of systemic (iv) luukemia L 1210. It is additionally effective against Gross leukemia even after oral administration and in a preliminary cardiotoxic test in mmymi C3H treated chronically iv it caused only heart damage. Compound 1a was studied in doxonubicin resistant (P 388 / DX) leukemia cells P388 in vitro and in vivo. Doxooubicin (DX) resistant leuknic cells P 388 Schabel) are maintained by serial transmission on DX i.p. For experimental purposes, BDD-1 mice were injected with 10 4 leukemia cells i.p. and mice were treated with i.p. one day after inoculation of the tumor. The results presented in Table 7 show that daunorubicin (DKR) was not effective against this tumor, while Compound 1a increased the survival rate of 0.8 mg / kg of the treated subjects with a counter-dose of 0.8 mg / kg.

Leuknic cells P388 and P388 / DX were obtained from ascites fluid m tekut and adapted to grow in suspension in vitrp. Cytotoxic assays were performed by exposing cells to various terminators for 48 hours; at the end of the exposure period, cells were counted on a Coult.er cell counter and the IC 50 was calculated (a dose that results in a 50¾ reduction in cell numbers compared to untreated controls). The results shown in Table 8 show that Ia was about twice as cytotoxic. than DNRs on P388 leukemia cells and very effective on P388 / DX cells, while DNRs are 163-152 times less potent in terms of resistance than sensitivity. .

Compound 1a was further monitored for carotid mammary carcinoma C3H. My2! with measurable tumor (third generation grafts) were treated once weekly for 4 weeks i.v. fabric le or DX. Normmini mice. were treated in parallel for toxicity. The results shown in Table 9 confirm that 1e was 10x more potent than DX and had significant antitumor efficacy in this experimental system at non-toxic doses, while DX was toxic.

Due to its good anti-breast cancer activity, compound 1a was evaluated against two solid tumors: colon 26 and colon 38, transplant s.c. MLLfVc 'and BDF-1 mice. Treatment started one day after tumor inoculation (time: **) or when the tumors were already hammable (progressive) and were administered i.v. once a week or every 6 days 3 to 4 times. Tumor growth was detected using a dividing device. Tumor-free mice were treated in parallel to assess toxicity and were observed for 90 days. The results of these experiments are shown in Table 10. Against early colon 26, it was much more effective at the maximum tolerated dose of 0.9 mg / kg / day than DX at the maximum tolerated dose.

7.5 mg / kg / day. Against advanced colon 26, Ie was nontoxic at the maximum dose tested 0.7 mg / kg / day and provided greater inhibition of tumor growth than DX at the maximum tolerated dose of 6 mg / kg / day. In advanced colon 38 at the maximum dose tested of 0.9 mg / kg / day, Ie was as effective as DX 9 mg / kg / day in inhibiting tumor growth, but resulted in increased survival.

In conclusion, all the data presented here confirm that compounds ia and Ie are extremely interesting novel anthracyclines, characterized by high potency, potency when administered orally, potency against anthracycline resistant (Ia) tumors, potency against solid tumors exceeding DX and without cardiotoxicity ( Ie).

Table 1

In vitro colony inhibition assay against Hela cells (24 hour treatment)

compound Dose ng / ml - (mg / ml) DUR 12.5 42 6.2 66 ~ 12 3.1 121 Ia 25 0 6.2 0 - 2,5 1.5 73 DX 12.5 20 May 6.2 79 ~ z9 3.1 177 Ie 10 0 2.5 9.9 1 0.62 82 • 0.15 84

^and colony no. % of untreated controls.

Table 2

Anti-tumor efficacy in leukemia P388 i.p. first day treatment

Compound, Dose (m ^ / ^/ kg) l '/ C ^a _ LTS ^b Toxic wrtrt ^c

DHR ^d 2.9 154 0/10 0/10 4.4 140, 154 0/20 4/20 6.6 109, 163 0/20 13/20 Ia 0.5 127 0/10 0/10 0.64 127 0/10 0/10 0.3 172, 127 0/20 1/20 1.0 145 o / it 0/10 1.3 95 0/10 10/10 DX 4.4 180 0/10 0/10 6.6 200 2/10 0/10 10,0 ^e 315 4/10 0/10 Ie 0.44 130 0/10 0/10 0.66 215 0/10 0/10 M 250 0/7 1/7 b'5. 245 2/10 4/10

^and mean ^and 3 survival of treated mice / present survival time of controls x'100 ^ louhodo ^ (3 ⁶⁰ days) c

evaluation based on autopsy findings on dead mice Data from two ^{TI p} of ^the USU e ^^ I ^ (^: s maximmání 'DX tolerated dose in this experimental system,

Table 3

Efficacy of Ia against Gross leukemia.

Submission treatment

Seznam3

Compound mg / kg / day

T / C ^b %

Toxic death

i. v. 1 DNR 10 133, 150 0/20 15 Dec 175 175, 166 3/30 22.5 208, 191, 216 6/30 i.v. 1 Ia 0.58 Í16 0/10 0.76 133 0/10 1.0 158, 166 0/20. 1.25 to 1.3 183, 208 0/20 1.56 100 ALIGN! 9/10 1, .95 116 6/10

235979 ⁸

Table 3-continued

Treatment T / C ° Toxic death ^c

Poddání Seznam® Compound m / kg / day % oral 1 1.1 133 0/10 1,25 to 1.3 133, 166 1/20 1.56 to 1.6 166, 166 3/20 1.95 to 2.0 1 175, 183 2/20 oral 1,2,3 4-desmetho- 1.31 125 0/10 xy DNR 1.58 to 1, 46 1'33, 150 1/20 1.9 133, 190 1/20 2.5 210 2/10 3.3 140 6/10 oral 1,2,3 La 0.44 133 0/9 0.66 183 0/10 1.0 200, 220 9/20 1,25 140 8/10

^and dn; y after tumor inotilation, ^{b, c} see Table ²

Efficacy for Gross Leukemia

Lé Podlálí čba " Compound mg / kg T / C% Tocical Death® i.V. DX 10 200 28 13 200, 216 2/18 16.9 250, 266 3/18 AND· 1.0 183, 233 0/18 1.3 192, 208 4 / 1Θ r 1.7 217/200 7/18 2.2 142 7/10 oral Ie 1.0 125 0/8 1.3 150 0/8 1.7 166 0/8 2.5 166 0/8

"On the first day after tumor ^{b, c,} see ^t and ^cell u ²

Table 5

Activity against leukemia L 1210

L 1210

inoculum Therapy Compound m / kg T / C % LTS ^{b T} oxic ^a l ^c úmtí i.p. i.p. DX 4.4 150 0/9 0/9 6.6 150 0/10 1/10 10.0 162 0/10 1/10 Ie 0.03 162 2/10 0/10 1.0 187 1/10 1/10 1,2 393 4/10 3/10 .and. IN. i.V. DX 10.0 120 0/10 0 / 1.0 p 13.0 120 0/10 0/10 16.9 133 0/10 0/10 Ie 1, 0 200 0/10 0/10 1.3 173 0/10 0/10 1.7 »580 5/10 0/10

a, b, c - see Table 2

Table 1: k and 6

Efficacy against C3H mammary carcinoma toxicity and cardiac toxicity of Le compared to DX

Mass with tumor T / C ^d % Mice without tumors ώ ^e ^ ί damage sr ^d ce ^F and V n. G. N. G. Compound m / k day Growth Inhibition of tumor growth ”% MST ^C tumors% • 4 845 53 - - - - DX 6 318 93 77 145 n.d. 7.5 277 94 74 140 2/3 4/4 1.3 _ 5/5 1.5 Ie 0.4 1 740 64 65 123 n.d. 0.6 748 85 76 143 n.d. 0.75 344 93 81 153 1/4 0/5 0 2/5 0.2

Explanatory Notes to Table 6;

hmoOnoat tumor ^and 43rd day after implantation (hmotnost.nádoru initially dispensaries x 100) ^{00 b} 1 - [N ^Aad growth oru-treated Si / tumor growth of controls x ^L 00j

0průměrný survival time (in '.dnech)' ^ dprŮ reverse to ^NO and 1 H-treated p2Se ^{EI-width-tert-reverse} to ^No and survival Koo ^t гol. x 1ДО “observation for 90 days f *

A = atrial atrium, V - ventricular (ventrictU.us), n - number of hearts appearing damaged / total, G = degree of damage

Table 7

Effect on doxorubicin-resistant P388 leukemia in vivo

Compound Dose (ag / kg) T / C ^and % LTS ^b Toxic death® DNR 2.9 93 0/10 0/10 4.4 87 0/10 1/10 6.6 84 0/10 3/10 Ia 0.53 133 0/10 0/10 0.8 142 1/10 0/10 ^1,2 106 0/10 4/10

"Average time of treated mice / průmšrná pířežX rd time controls x 100 ^b Tangible ^about BE přeiití (360 days) chodnocení based on autopsy findings on dead mosses

Table 8

Effect on sensitive and doxorrbicin-resident t3Θ8 in vitro

Compound ^ID 50 _by Р38в ^с P388 / DX ^d R ^e DNR 5,8,2,3 950,350 163.152 le 0.35, 1.3 1,4,5 4,3,8 "Data from two of ^{the BDA} and the Head attempts to 50% of the number count ^b un§ ^k in comparison with untouched controls

cieukemické P388 cells sensitive to DX leiikemické bunk ^ ^y ^ Ρ3Θ8 the resistant to DX Omer% between Id ^ qu ^P388 / DX ^{and 1388}

Table 9

Efficacy of Ie against mammary gland carcinoma in C3H mice

Compound m / kg / day hmoonost (mg) Mice 3 tumors MST ^C T / C ^d % Mice without tumors úwtJ ^s ® tumor T / C ^%% 651 115.5 0/10 DX 6.0 238 37 149 129 1/10 7.5 209 32 100 ALIGN! 87 7/10 Ie 0.6 422 65 118 103 0/10 0.75 363 40 126.5 110 0/10

a) evaluated 1 week after the last treatment, measured by a tapper

(b) tumor morbidity in treated masses / tumor morbidity in controls x 100

c) average survival time (in days)

d) mean survival time for treated carcasses / mean survival time for controls (x 100)

e) have been observed for 90 days

Table 10

Influence of Ie and DX on two transplent colon adenocarcinomas in masses

Stadim® tumor Seznam ^b Compound Dose (m ^ kg) ^c inhibition T / C ^d % Toxic tonnage colon 26 early q7dx4 DX 6 56 217 0/10 7.5 82 224 0/10 9.3 81 161 9/10 Ie 0.6 81 258 0/10 0.75 85 227 0/10 0.9 93 246 1/10 p ^ Ja ^ c ^ eyes q6dx3 . DX 6 34 237 0/9 9 62 237 4/9 Iž 0.6 48 232 0/9 0.7 52 195 0/9 colon 38 fields * oCčlé q7dx4 DX 6 65 92 0/10 9 83 144 1/10 Iž 0.6 55 133 0/10 0.75 60 129 0/10 ° 19 81 184 0/10

<

^{and the} time of the beginning of treatment due to the development of tumor ^b days after iv administration INM ^ ce growth on ^d oru compared to non-platoon controls ^ average ^d both survival ^{treatment of tumors} enýc ^{h we the} I / ^P In average time read konrrol, ^χ 100 ^ otaocení MRSI ^b ez n ^and DOR ^{have on Lac} enýc ^hp faraleln ^E and ^P ozorovaných RH ^for 90 days

Claims (1)

OBJECT OF THE INVENTION wherein hydrogen is ^R 1 is hydrogen from ^r 2 · R 3 A method for producing formula I or Metty !, or hydroíqrl one - is methoxy and the other represents a doxoruhicinu, of hydrogen, (I) vyznačujjcí in that the ^{4-demethoxy-c} daunon Inon or 2,3- ^d imethyrl "4deemetho: yyddainiomycinon dissolved in anhydrous metlhOenidchloridu, is reacted at room temperature with 2,3,6-tiddeo:> yr-Зttrlflrocetetemddo-4-0-L-metlyrl lχxo-hθxo {yr anosyl ^4-c ^ ťLorddee or 2.3, 4-O-methyl-3-trifluoromethyl-4-O-methyl-L-aryloxyhexopyranosulfonate in the presence of silver trifluoromethanesulphonate and molecular sieves to form the corresponding N trifluoroacetyl protected alpha-glycosides, is removed with an N-trifluoroacetyl salt. aqueous sodium hydroxide to give the corresponding daunnoribicin derivatives of formula I, wherein X is hydrogen, which are optionally converted to the corresponding doxorablcin derivatives of formula I wherein X is the hydroxyl group by bromination and by acting on the 14-iroo-iottreedial thus formed. compounds descendants of sodium formate.