Long-range effect of 17-substituents in 3-oxo steroids on 4,5-double bond hydrogenation

Article abstract of DOI:10.1135/cccc19981528

The long-range effect of substituents in the 17-position on the hydrogenation of double bond of the steroidal Δ⁴-3-ketones in acetic acid on a platinum catalyst is described in a series of testosterone (1) and epitestosterone (5) esters with carboxylic acids of varying alkyl chain length. The ratio 5α-to 5β-products is affected by the nature of substituents in the position 17.

Full text of DOI:10.1135/cccc19981528

1528
Sidova, Stransky, Kasal, Slavikova, Kohout:
LONG-RANGE EFFECT OF 17-SUBSTITUENTS IN 3-OXO STEROIDS
ON 4,5-DOUBLE BOND HYDROGENATION*
1
2
3
Romana SIDOVA, Karel STRANSKY , Alexander KASAL , Barbora SLAVIKOVA
and Ladislav KOHOUT **
4,
Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic,
166 10 Prague 6, Czech Republic; e-mail: 1 stransky@uochb.cas.cz, 2 kasal@marilyn.uochb.cas.cz,
3 barbora@uochb.cas.cz, 4 kohout@uochb.cas.cz
Received February 20, 1998
Accepted April 25, 1998
Dedicated to Dr Jan Fajkos on the occasion of his 75th birthday.
The long-range effect of substituents in the 17-position on the hydrogenation of double bond of the
steroidal ∆4-3-ketones in acetic acid on a platinum catalyst is described in a series of testosterone (1)
and epitestosterone (5) esters with carboxylic acids of varying alkyl chain length. The ratio 5α- to
5β-products is affected by the nature of substituents in the position 17.
Key words: Steroids; Long-range effect; 5α/5β Ratio; Hydrogenation; Circular dichroism; Gas chro-
matography.
Long-range effects of steroid 17-substituents on an A/B ring junction have been de-
scribed2–4. The outcome of equilibration of various 17-substituted 2β,3β-dihydroxy 6-oxo
steroids may be interpreted in terms of conformational transmission: equilibrium constants
were substantially influenced by substituents in the position 17 (K5β/5α = 0.56–7.06).
Long-range effects of C-17 substituents on the stereochemical course of hydrogena-
tion of a steroidal 4,5-double bond have not been systematically studied. A few
examples of palladium-catalyzed hydrogenation of 4,5-unsaturated 3-oxo steroids were
described5–7 and the 5 configuration was shown to depend on the nature of C-17 substi-
tuents. Much more attention, however, was paid to the influence of solvent type and pH
of the hydrogenation media8.
We anticipated that hydrophobic interactions of the side chain in the position 17
might enhance the approach to the ∆4 double bond, of hydrogen from the opposite side
* Part CCCXCVII in the series On Steroids; Part CCCXCVI see ref.1.
**The author to whom correspondence should be addressed.
Collect. Czech. Chem. Commun. (Vol. 63) (1998)

On Steroids
1529
of the molecule. The present paper9,10 reports on the influence of C-17 substituents on
the platinum-catalyzed hydrogenation of the 3-oxo-4-ene steroids in acetic acid.
Substrates for the hydrogenation were prepared by acylation of testosterone (1) and
epitestosterone (5) with carboxylic acids of varying length of carbon chain (Scheme 1).
OH
OR
(i)
O
O
1
2
(ii)
OR
OR
O
O
H
H
3
4
OH
OR
(i)
O
O
5
6
(ii)
OR
OR
O
O
H
H
7
8
In formulae 2-4 and 6-8 :
a,
b,
c,
f,
g,
h,
R = COH
R = COCH
R = COCH CH
R = CO(CH ) CH
2 8 3
R = CO(CH ) CH
2 10
3
3
3
3
R = CO(CH ) CH
2
3
2 12
d, R = CO(CH ) CH i, R = CO(CH ) CH
2 2
3
2 16
e, R = CO(CH ) CH
2 5
3
(i) RCOCl or (RCO) O/pyrdine; (ii) 1. Pt/AcOH, 2. Jones/acetone
2
SCHEME 1
Collect. Czech. Chem. Commun. (Vol. 63) (1998)

1530
Sidova, Stransky, Kasal, Slavikova, Kohout:
The acylation was carried out by overnight treatment of 1 and 5 with corresponding
acid anhydrides or chlorides in pyridine at ambient temperature. A list of the substrates
includes esters of formic (2a and 6a), acetic (2b and 6b), propionic (2c and 6c), butyric
(2d and 6d), heptanoic (2e and 6e), decanoic (2f and 6f), dodecanoic (2g and 6g),
tetradecanoic (2h and 6h) and octadecanoic (2i and 6i) acids.
All the esters were hydrogenated under the same conditions (Adams catalyst, acetic
acid, ambient temperature). Since the 3-oxo group was partially reduced in the course
of the hydrogenation, reaction mixture was in each case treated with Jones reagent.
Obtained 5α and 5β isomers were separated by chromatography on a column of silica
gel or by preparative thin layer chromatography. The structure of known products was
proved by comparison with authentic samples. In case of unknown compounds 3i, 4i,
7b, 8b, 7i and 8i, the C-5 configuration was assigned on the basis of CD spectra which
were correlated with the spectra of 5α-cholestan-3-one (9) and 5β-cholestan-3-one (10)
(Table I).
1H NMR spectra of the prepared compounds are listed in Table II. We have found a
one-proton triplet (of apparently one of H-4 proton) at 2.7 ppm (J = 14 Hz) in all the
5β derivatives studied (i.e., in spectra of compounds 4i, 8b, 8i) but not in the corre-
sponding 5α isomers (3i, 7b, 7i). The presence of this triplet was therefore taken as an
evidence of the 5β configuration in 3-oxo steroids in the other ketones produced (4a to
4i and 8a to 8i). Compounds 3a to 3i and 7a to 7i did not shown the triplet. Its origin
is described in detail elsewhere11.
Quantitative analysis of the mixture of 5α and 5β isomers in reaction mixtures was
based on gas chromatography which was carried out under different conditions (Table III).
Table III also displays the effect of C-17 substituents on the ratio of 5α/5β isomers
formed. Both the C-17 configuration and the length of the 17-acyloxy group play a role
TABLE I
CD spectra of 5α- and 5β-3-oxo steroids
Compound
Configuration
∆ε
λ, nm
5α-Cholestan-3-one (9)
5β-Cholestan-3-one (10)
Octadecanoate 3i
Octadecanoate 4i
Acetate 7b
5α
5β
5α
5β
5α
5β
5α
5β
+1.08
–0.47
+0.50
–0.20
+0.53
–0.23
+0.51
–0.37
294
293
294
294
296
293
293
294
Acetate 8b
Octadecanoate 7i
Octadecanoate 8i
Collect. Czech. Chem. Commun. (Vol. 63) (1998)

On Steroids
1531
TABLE II
1H NMR spectra of compounds prepared
Compound
H-18a
H-19a
H-4b
H-17
Other signals
2a
2b
2c
2d
2e
2f
0.99
0.84
0.84
0.83
0.85
0.83
0.84
0.84
0.84
0.81
0.84
0.80
0.81
0.81
0.81
0.81
0.81
0.80
0.81
0.80
0.81
0.80
0.80
0.80
0.81
0.80
0.80
0.82
0.79
0.80
0.79
0.75
0.76
1.21
1.19
1.19
1.18
1.20
1.18
1.19
1.19
1.19
1.02
1.04
1.01
1.03
1.02
1.03
1.01
1.03
1.01
1.03
1.01
1.03
1.02
1.03
1.02
1.03
1.01
1.03
1.19
1.19
1.19
1.19
1.15
1.16
5.75
5.70
5.75
5.72
5.74
5.75
5.75
5.75
5.74
–
4.83c
4.60c
4.61c
4.62c
4.62c
4.60c
4.62c
4.62c
4.61c
4.62c
4.75c
4.60c
4.60c
4.60c
4.62c
4.61c
4.61c
4.60c
4.62c
4.60c
4.61c
4.60c
4.62c
4.60c
4.63c
4.63c
4.65c
4.95d
4.82d
4.82d
4.82d
4.78d
4.80d
8.07f
2.04g
0.94h
0.90h
0.87h
2g
2h
2i
0.90h
0.89h
0.90h, 1.25i
8.08f
3a
4a
3b
4b
3c
4c
3d
4d
3e
4e
3f
–
8.08f, 2.68e
2.04g
2.04g, 2.70e
1.14h
1.14h, 2.70e
0.95h, 1.25i
0.95h, 1.25i, 2.68e
0.88h, 1.25i
0.88h, 1.25i, 2.69e
0.88h, 1.25i
0.86h, 1.25i, 2.70e
0.88h, 1.25i
0.88h, 1.25i, 2.70e
0.88h, 1.25i
0.88h, 1.25i, 2.70e
1.25i
–
–
–
–
–
–
–
–
–
4f
–
3g
4g
3h
4h
3i
–
–
–
–
–
4i
–
1.25i, 2.70e
8.06f
2.03g
6a
6b
6c
6d
6e
6f
5.75
5.74
5.75
5.74
5.71
5.70
0.94h
0.82h
0.83h
Collect. Czech. Chem. Commun. (Vol. 63) (1998)

1532
Sidova, Stransky, Kasal, Slavikova, Kohout:
TABLE II
(Continued)
Compound
H-18a
H-19a
H-4b
H-17
Other signals
6g
6h
6i
0.81
0.81
0.81
0.79
0.79
0.76
0.76
0.77
0.76
0.76
0.75
0.76
0.75
0.76
0.76
0.79
0.76
0.76
0.77
0.76
0.74
1.21
1.21
1.20
1.02
1.03
1.01
1.03
1.02
1.03
1.02
1.02
1.02
1.02
1.02
1.03
1.02
1.03
1.02
1.04
1.02
1.01
5.78
5.78
5.76
–
4.82d
4.82d
4.85d
4.95d
4.92d
4.81d
4.85d
4.82d
4.81d
4.82d
4.82d
4.80d
4.80d
4.82d
4.82d
4.80d
4.82d
4.81d
4.82d
4.80d
4.80d
0.90h
0.89h
0.90h, 1.27i
8.06f
8.06f, 2.70e
2.03g
7a
8a
7b
8b
7c
8c
7d
8d
7e
8e
7f
–
–
–
2.03g, 2.70e
–
–
2.72e
0.95h, 1.25i
0.95h, 1.25i, 2.72e
0.87h, 1.25i
0.87h, 1.25i, 2.70e
0.88h, 1.25i
0.88h, 1.25i, 2.72e
1.25i
1.25i, 2.72e
0.88h, 1.25i
0.88h, 1.25i, 2.72e
0.90h, 1.25i
–
–
–
–
–
8f
–
7g
8g
7h
8h
7i
–
–
–
–
–
8i
–
0.87h, 1.23i, 2.70e
a
b
c
d
e
s, 3 H (CH3); s, 1 H; dd, 1 H, J = J′ = 6 (17α-H); d, 1 H, J = 6 (17β-H); t, 1 H, J = 14
f
g
h
i
(4α-H); s, 1 H (formate); s, 3 H (acetate); t, 3 H, J = 5–7 (CH3 of alkyl chain); broad s (CH2
of alkyl chain).
in controlling the hydrogenation course: in 17α-esters, the 5α/5β ratio decreases with
increasing length of alkyl chain of acyl group, whereas in 17β-esters, the ratio keeps
steady up to decanoate 2f and then rises sharply (except of the compound 3h; this
exception we are not able to explain). The difference between the stereochemistry of
corresponding 17α- and 17β-esters suggests that hydrophobic interactions may play a
role in hydrogenation of the esters: as the length of acyl groups becomes sufficient, the
one-side packing of the acyl chain on the steroid skeleton improves the approach from
the other side.
Collect. Czech. Chem. Commun. (Vol. 63) (1998)

On Steroids
1533
EXPERIMENTAL
Melting points were determined on an Electrothermal 9100 point apparatus and are uncorrected. Op-
tical rotations were measured at 25 °C on a Perkin–Elmer 141 MC polarimeter in chloroform and
[α]D values are given in ° (10–1 deg cm2 g–1). CD spectra were measured in dioxane (range 240 to
350 nm) on a Jobin Yvon Mark V instrument. IR spectra were measured in tetrachloromethane on a
Bruker IFS 88 (wavenumbers are given in cm–1) and 1H NMR spectra in deuteriochloroform solu-
tions on a Varian XL-200 (FT-mode, 200.04 MHz, internal standard tetramethylsilane) instruments.
Chemical shifts are given in ppm (δ-scale), coupling constants (J) in Hz. All values were obtained by
first-order analysis. Electron impact mass spectra were obtained with a ZAB-EQ spectrometer at 70 eV.
Gas chromatography was performed on an HP 5990A gas chromatograph (Hewlett–Packard, U.S.A.)
equipped with flame ionization detector and split-splitless injector. DB-1 column (30 m × 0.25 mm × 0.25 µm)
and hydrogen as a carrier gas were used. Column, injector and detector temperatures as well as pressures
of the carrier gas for every isomer and every mixture of isomers are given in detail elsewhere12.
TABLE III
Ratio of 5 isomers (in %) obtained by hydrogenation of testosterone esters and epitestosterone estersa
Ratio of 5 isomers
Starting compound
(number of carbon atoms
forming the acyl group)
5α
5β
2a (1)
33.1
32.9
23.9
31.2
30.2
32.2
40.8
29.5
50.8
22.4
16.7
20.3
17.9
10.8
12.1
10.6
11.3
10.8
66.9
67.1
76.1
78.8
79.8
67.8
59.2
70.5
49.2
77.6
83.3
79.7
82.1
89.2
87.9
89.4
88.7
89.2
2b (2)
2c (3)
2d (4)
2e (7)
2f (10)
2g (12)
2h (14)
2i (18)
6a (1)
6b (2)
6c (3)
6d (4)
6e (7)
6f (10)
6g (12)
6h (14)
6i (18)
a
Ratio was determined by gas chromatography analysis of reaction mixture under the conditions
given in Experimental.
Collect. Czech. Chem. Commun. (Vol. 63) (1998)

1534
Sidova, Stransky, Kasal, Slavikova, Kohout:
Column chromatography was performed on silica gel (60–120 µm), preparative thin-layer chromato-
graphy (PLC) on silica gel Woelm DC (200 × 200 × 0.7 mm), detection by spraying of the side strips
of the plates with sulfuric acid and heating or by spraying the plates with 0.2% morin solution in
methanol and UV detection. The identity of samples was checked by TLC, melting points, IR and 1H NMR
spectra.
A “usual working up” of the solution means washing with water, 5% aqueous potassium hydrogen
carbonate, water, drying over anhydrous sodium sulfate, filtering and evaporation of the solvent in
vacuo (at about 3 kPa) to dryness. The light petroleum was a fraction boiling at 40–62 °C.
General Procedure for Hydrogenation of Compounds 2a–2i and 6a–6i
Platinum oxide catalyst (20 mg) was added to a solution of compound (2a–2i and 6a–6i) (100 mg)
in acetic acid (5 ml) and stirred while passing hydrogenation by gas hydrogen for one hour. The
catalyst was filtered off, the reaction mixture poured into water, the product extracted with ether,
organic phase washed with water and 5% hydrochloric acid solution, and worked up as usual. Jones
reagent (0.5 ml) was added to a solution of product (100 mg) in acetone (20 ml). After 5 min pro-
pan-2-ol was added dropwise until the residue of Jones reagent was destroyed. The mixture was
poured into water, the product was extracted with ether and the extract was worked up as usual.
3-Oxoandrost-4-en-17β-yl Formate (2a)
The mixture of formic acid (4.0 ml, 106 mmol) and acetic anhydride (1.5 ml, 15.8 mmol) cooled to
0 °C was added to a solution of 1 (300 mg, 1.04 mmol) in pyridine (6 ml, 0 °C). The reaction mix-
ture was poured into water after standing overnight at laboratory temperature. The product was ex-
tracted with ether, the organic extract was washed with hydrochloric acid (10%, 2 × 30 ml) and then
worked up as usual. Chromatography of the residue (315 mg) on a thin layer of silica gel (light pe-
troleum–ether 1 : 1) afforded 295 mg (88%) of 2a, m.p. 170–172 °C, [α]D +72 (c 1.14) (ref.13 gives
m.p. 127–129 °C). IR spectrum: 1 721 (C=O, ester); 1 671 (C=O, ketone); 1 619 (C=C).
3-Oxo-5α-androstan-17β-yl Formate (3a) and 3-Oxo-5β-androstan-17β-yl Formate (4a)
Compound 2a (220 mg, 0.63 mmol) was hydrogenated and then treated with Jones reagent as given
above. Preparative layer chromatography of 180 mg of the residue (light petroleum–ether 3 : 2)
yielded 45 mg (22%) of lipophilic compound 3a, m.p. 142–144 °C (ethanol), [α]D +14 (c 1.12) (ref.14
gives m.p. 143–145 °C, [α]D +24). IR spectrum: 1 741 (C=O, formate); 1 716 (C=O, ketone). Work-
ing up of PLC with polar compound afforded 130 mg (62%) of compound 4a, m.p. 110–112 °C
(aqueous ethanol), [α]D +21 (c 2.41). IR spectrum: 1 740 (C=O, formate); 1 715 (C=O, ketone). For
C20H30O3 (318.5) calculated: 75.43% C, 9.50% H; found: 75.60% C, 9.32% H.
3-Oxo-5α-androstan-17β-yl Acetate (3b) and 3-Oxo-5β-androstan-17β-yl Acetate (4b)
3-Oxoandrost-4-en-17β-yl acetate (2b) (200 mg, 0.6 mmol) was hydrogenated and then treated with
Jones reagent as given above. Chromatography of 180 mg of the residue (40 g of silica gel, light
petroleum–ether 1 : 1) yielded 47.6 mg (24%) of compound 3b, m.p. 159–162 °C, [α]D +24 (c 1.31) (ref.15
gives m.p. 158–159 °C, [α]D +26). IR spectrum: 1 740 (C=O, acetate); 1 716 (C=O, ketone). Continu-
ation of the chromatography yielded 115 mg (61%) of polar compound 4b, m.p. 142–146 °C, [α]D
+21 (c 1.17) (ref.16 gives m.p. 140–142 °C, [α]D +20.5). IR spectrum: 1 737 (C=O, acetate); 1 718
(C=O, ketone).
Collect. Czech. Chem. Commun. (Vol. 63) (1998)

On Steroids
1535
3-Oxo-5α-androstan-17β-yl Propionate (3c) and 3-Oxo-5β-androstan-17β-yl Propionate (4c)
3-Oxoandrost-4-en-17β-yl 3-propionate (2c) (170 mg, 0.49 mmol) was hydrogenated and then treated
with Jones reagent as given above. PLC of the residue (163 mg) on 6 plates (light petroleum–ether 7 : 3)
yielded 32 mg (19.6%) of compound 3c, m.p. 112–122 °C (methanol), [α]D +19 (c 1.10) (ref.17 gives
m.p. 119–123 °C). IR spectrum: 1 740 (C=O, propionate); 1 716 (C=O, ketone).
Working up of the PLC zones from the proceeding paragraph afforded 115.7 mg (71%) oily com-
pound 4c, [α]D +29 (c 2.43). IR spectrum: 1 737 (C=O, propionate); 1 718 (C=O, ketone). For
C22H34O3 (346.5) calculated: 76.26% C, 9.89% H; found: 76.02% C, 9.97% H.
3-Oxoandrost-4-en-17β-yl Butyrate (2d)
The butyryl chloride (0.5 ml, 4.8 mmol) was added to a solution of 1 (400 mg, 1.39 mmol) in py-
ridine (8 ml). After standing overnight at laboratory temperature the reaction mixture was poured on
ice. The product was extracted with ether and the organic extract was washed with hydrochloric acid
(10%, 2 × 30 ml) and worked up as usual. Crystallization from methanol yielded 219 mg (44%) of
product 2d, m.p. 109–111 °C, [α]D +78 (c 1.71) (ref.13 gives m.p. 111–113 °C). IR spectrum: 1 734
(C=O, butyrate); 1 678 (C=O, ketone); 1 619 (C=C).
3-Oxo-5α-androstan-17β-yl Butyrate (3d) and 3-Oxo-5β-androstan-17β-yl Butyrate (4d)
Compound 2d (150 mg, 0.42 mmol) was hydrogenated and then treated with Jones reagent as given
above. PLC of the residue (135 mg) on 5 plates (light petroleum–ether 1 : 1) yielded 30.5 mg (20%)
of lipophilic compound 3d, m.p. 80–83 °C (ethanol). IR spectrum: 1 734 (C=O, butyrate); 1 717
(C=O, ketone). For C23H36O3 (360.5) calculated: 76.62% C, 10.06% H; found 76.22% C, 9.79% H.
Zones from PLC with the polar compound afforded after working up 85.7 mg (57%) of polar com-
pound 4d, m.p. 86–90 °C. IR spectrum: 1 732 (C=O, butyrate); 1 718 (C=O, ketone). For C23H36O3
(360.5) calculated: 76.62% C, 10.06% H; found: 76.02% C, 9.97% H.
3-Oxoandrost-4-en-17β-yl Heptanoate (2e)
Heptanoyl chloride (0.7 ml, 4.5 mmol) was added to a solution of 1 (400 mg, 1.39 mmol) in pyridine
(8 ml). After standing overnight at laboratory temperature the reaction mixture was poured into cold
water. The product was extracted with ether and the organic extract was washed with hydrochloric
acid (10%, 2 × 30 ml) and then worked up as usual. Crystallization from methanol yielded 315 mg
(57%) of ester 2e, m.p. 35–36 °C [α]D +74 (c 2.13) (ref.18 gives m.p. 36–37 °C, [α]D +77). IR spec-
trum: 1 733 (C=O, heptanoate); 1 678 (C=O, ketone); 1 620 (C=C).
3-Oxo-5α-androstan-17β-yl Heptanoate (3e) and 3-Oxo-5β-androstan-17β-yl Heptanoate (4e)
Compound 2e (200 mg, 0.50 mmol) was hydrogenated and then treated with Jones reagent as given
above. PLC of the residue (193 mg) on 8 plates (light petroleum–ether 7 : 3) yielded 48.3 mg (25%)
of compound 3e, m.p. 89–91 °C, [α]D +25 (c 2.0) (ref.19 gives m.p. 92 °C). IR spectrum: 1 731
(C=O, heptanoate); 1 718 (C=O, ketone).
Zones with the polar compound from PLC plates after working up afforded 139 mg (69%) of com-
pound 4e which resisted all attempts to crystallize, [α]D +17. IR spectrum: 1 732 (C=O, heptanoate); 1 717
(C=O, ketone). For C26H42O3 (402.6) calculated: 77.56% C, 10.51% H; found: 77.02% C, 10.97% H.
Collect. Czech. Chem. Commun. (Vol. 63) (1998)

1536
Sidova, Stransky, Kasal, Slavikova, Kohout:
3-Oxoandrost-4-en-17β-yl Decanoate (2f)
The decanoyl chloride (1.0 ml, 4.8 mmol) was added to a solution of 1 (400 mg, 1.39 mmol) in
pyridine (8 ml). After standing overnight at laboratory temperature the reaction mixture was poured
on ice. The product was extracted with ether and the organic extract was washed with hydrochloric
acid (10%, 2 × 30 ml) and then worked up as usual. Chromatography of the residue (882 mg) on a
column of silica gel (50 g, light petroleum–ether 10 : 3) afforded 522 mg (85%) of decanoate 2f,
m.p. 58–59 °C (ethanol), [α]D +74 (c 0.99) (ref.20 gives m.p. 54–56 °C, [α]D +71). IR spectrum: 1 733
(C=O, decanoate); 1 678 (C=O, ketone); 1 616 (C=C).
3-Oxo-5α-androstan-17β-yl Decanoate (3f) and 3-Oxo-5β-androstan-17β-yl Decanoate (4f)
Compound 2f (200 mg, 0.45 mmol) was hydrogenated as given above and then treated with Jones
reagent. The reaction mixture was worked up as usual. PLC of the residue (182 mg) on 8 preparative
plates (light petroleum–ether 7 : 3) yielded 32 mg (16%) of oily lipophilic compound 3f, [α]D +35 (c 1.61).
IR spectrum: 1 732 (C=O, decanoate); 1 718 (C=O, ketone). For C29H48O3 (444.7) calculated:
78.33% C, 10.88% H; found: 77.15% C, 9.98% H.
Working up of the PLC plates of the previous paragraph afforded 131 mg (67%) of the oily polar
compound 4f, [α]D +17 (c 1.39). IR spectrum: 1 732 (C=O, decanoate); 1 719 (C=O, ketone). For
C29H48O3 (444.7) calculated: 78.33% C, 10.88% H; found: 78.62% C, 11.02% H.
3-Oxoandrost-4-en-17β-yl Dodecanoate (2g)
The dodecanoyl chloride (1.0 ml, 4.3 mmol) was added to a solution of 1 (400 mg, 1.39 mmol) in
pyridine (8 ml). After standing overnight at laboratory temperature the reaction mixture was poured
into cold water. The product was extracted with ether and the organic extract was washed with hy-
drochloric acid (10%, 2 × 30 ml) and then worked up as usual. Chromatography of the residue (670 mg)
on the column of silica gel (50 g, light petroleum–ether 7 : 3) afforded 616 mg (94%) of dodecanoate
2g, m.p. 146–149 °C (aqueous ethanol) after recrystallization at 80 °C, [α]D +73 (c 1.19). IR spec-
trum: 1 733 (C=O, dodecanoate); 1 679 (C=O, ketone); 1 619 (C=C). For C31H50O3 (470.7) calcu-
lated: 79.10% C, 10.71% H; found: 79.13% C, 10.88% H.
3-Oxo-5α-androstan-17β-yl Dodecanoate (3g) and 3-Oxo-5β-androstan-17β-yl Dodecanoate (4g)
Compound 2g (90 mg, 0.19 mmol) was hydrogenated as given above and then treated with Jones
reagent. The reaction mixture was worked up as usual. PLC of the residue (81 mg) on 4 preparative
plates (light petroleum–ether 7 : 3) yielded 32 mg (37%) of less polar compound 3g, [α]D +39 (c 0.22).
IR spectrum: 1 733 (C=O, dodecanoate); 1 717 (C=O, ketone). For C31H52O3 (472.8) calculated:
78.76% C, 11.09% H; found: 79.01% C, 11.33% H.
PLC from the previous paragraph afforded 48 mg (55.5%) of the polar compound 4g, [α]D +19 (c 0.55).
IR spectrum: 1 732 (C=O, dodecanoate); 1 717 (C=O, ketone). For C31H52O3 (472.8) calculated:
78.76% C, 11.09% H; found: 78.61% C, 11.12% H.
3-Oxoandrost-4-en-17β-yl Tetradecanoate (2h)
Tetradecanoyl chloride (1.0 ml, 3.7 mmol) was added to as solution of 1 (300 mg, 1.04 mmol) in
pyridine (8 ml). After standing overnight at laboratory temperature the reaction mixture was poured
into cold water. The product was extracted with ether and the organic extract was washed with hy-
drochloric acid (10%, 4 × 20 ml) and then worked up as usual. Chromatography of the residue (650 mg)
on a column of silica gel (40 g, light petroleum–ether 6 : 1) afforded 410 mg (79%) of tetradecanoate
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2h, m.p. 63–64 °C (ethanol–water 5 : 1), [α]D +67 (c 3.01). IR spectrum: 1 734 (C=O, tetradeca-
noate); 1 678 (C=O, ketone); 1 619 (C=C). For C33H54O3 (498.8) calculated: 79.46% C, 10.91% H;
found: 79.02% C, 11.12% H.
3-Oxo-5α-androstan-17β-yl Tetradecanoate (3h) and 3-Oxo-5β-androstan-17β-yl Tetradecanoate (4h)
Compound 2h (100 mg, 0.20 mmol) was hydrogenated as given above and then treated with Jones
reagent. The reaction mixture was worked up as usual. PLC of the residue (90 mg) (3 plates, light
petroleum–ether 9 : 1) afforded 24 mg (24%) of oily less polar compound 3h, [α]D +27 (c 1.18). IR
spectrum: 1 733 (C=O, tetradecanoate); 1 716 (C=O, ketone). For C33H56O3 (500.8) calculated:
79.14% C, 11.27% H; found: 79.32% C, 10.98% H.
PLC from the previous paragraph afforded 57 mg (57%) of the oily polar compound 4h, [α]D +19
(c 1.32). IR spectrum: 1 732 (C=O, tetradecanoate); 1 716 (C=O, ketone). For C33H56O3 (500.8) cal-
culated: 79.14% C, 11.27% H; found: 79.44% C, 11.32% H.
3-Oxoandrost-4-en-17β-yl Octadecanoate (2i)
Octadecanoyl chloride (600 mg, 1.9 mmol) was added to a solution of 1 (220 mg, 0.76 mmol) in
pyridine (9 ml). After standing overnight at laboratory temperature the reaction mixture was poured
into cold water. The product was extracted with ether and the organic extract was washed with hy-
drochloric acid (10%, 2 × 30 ml) and then worked up as usual. Crystallization from acetone yielded
octadodecanoate 2i (400 mg, 94%), m.p. 80–81 °C (aqueous ethanol), [α]D +57 (c 1.11) (ref.13 gives
m.p. 79–80 °C). IR spectrum: 1 734 (C=O, octadecanoate); 1 678 (C=O, ketone); 1 619 (C=C).
3-Oxo-5α-androstan-17β-yl Octadecanoate (3i) and 3-Oxo-5β-androstan-17β-yl Octadecanoate (4i)
Compound 2i (60 mg, 0.11 mmol) was hydrogenated as given above and then treated with Jones
reagent. The reaction mixture was worked up as usual. PLC of 56 mg of the residue at three plates
(light petroleum–ether 3 : 2) afforded product which on crystallization from light petroleum with 5%
of acetone yielded 17 mg (28%) of less polar octadecanoate 3i, m.p. 69–71 °C. IR spectrum: 1 733
(C=O, octadecanoate); 1 717 (C=O, ketone); 1 174, 1 029 (C–O). Mass spectrum, m/z (%): 556 (M+, 50),
486 (8), 289 (6), 272 (100), 267 (21), 255 (20), 202 (18), 149 (28). For C37H64O3 (556.9) calculated:
79.51% C, 11.90% H; found: 79.85% C, 12.23% H.
Working up of the PLC plates with the polar product afforded 19 mg (32%) of the octadecanoate 4i,
m.p. 59–62 °C (light petroleum with 5% of acetone). IR spectrum: 1 732 (C=O, stearate); 1 718
(C=O, ketone); 1 174, 1 023 (C–O). Mass spectrum, m/z (%): 556 (M+, 11), 486 (8), 289 (10), 272 (73),
267 (22), 255 (51), 202 (58), 149 (40), 71 (100). For C37H64O3 (556.9) calculated: 79.51% C, 11.90% H;
found: 80.03% C, 12.13% H.
3-Oxoandrost-4-en-17α-yl Formate (6a)
The mixture of formic acid (4.00 ml, 106 mmol) and acetic anhydride (1.50 ml, 15.8 mmol) cooled
to 0 °C was added a solution of epitestosterone 5 (300 mg, 1.04 mmol) in pyridine (6 ml, 0 °C).
After standing overnight at laboratory temperature the reaction mixture was poured into water. The
product was extracted with ether and the organic extract was washed with hydrochloric acid (10%,
2 × 30 ml) and then worked up as usual. Chromatography of the residue (326 mg) on a column of silica
gel (50 g, light petroleum–ether 1 : 1) afforded 298 mg (90%) of 6a, m.p. 168–170 °C. IR spectrum:
1 727 (C=O, formate); 1 679 (C=O, ketone); 1 619 (C=C); 1 215 (C–O). For C20H28O3 (316.4) cal-
culated: 75.91% C, 8.92% H; found: 76.03% C, 9.12% H.
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Sidova, Stransky, Kasal, Slavikova, Kohout:
3-Oxo-5α-androstan-17α-yl Formate (7a) and 3-Oxo-5β-androstan-17α-yl Formate (8a)
Compound 6a (220 mg, 0.7 mmol) was hydrogenated and then treated with Jones reagent as given
above. The aliquot (34 mg) of the residue (182 mg) on PLC separation (6 plates, light petroleum–ether
4 : 1, double development) yielded 24 mg (11%) of formate 7a, m.p. 153–166 °C (ethanol). IR spec-
trum: 1 739 (C=O, formate); 1 716 (C=O, ketone). For C20H30O3 (318.5) calculated: 75.43% C,
9.50% H; found: 75.14% C, 9.41% H.
Working up of PLC plates with polar compound afforded 139 mg (63%) of formate 8a, m.p. 150–152 °C.
IR spectrum: 1 740 (C=O, formate); 1 715 (C=O, ketone). For C20H30O3 (318.5) calculated: 75.43% C,
9.50% H; found: 75.81% C, 9.20% H.
3-Oxoandrost-4-en-17α-yl Acetate (6b)
Acetic anhydride (0.67 ml, 7.1 mmol) was added to the solution of 5 (220 mg, 0.76 mmol) in py-
ridine (5 ml). After standing overnight at laboratory temperature the reaction mixture was poured into
cold water. The product was extracted with ether and the organic extract was washed with hydro-
chloric acid (10%, 3 × 20 ml) and then worked up as usual. Crystallization from methanol yielded
acetate 6b (210 mg, 62%), m.p. 120–121 °C (ref.21 gives m.p. 114–115 °C). IR spectrum: 1 732
(C=O, acetate); 1 678 (C=O, ketone); 1 619 (C=C).
3-Oxo-5α-androstan-17α-yl Acetate (7b) and 3-Oxo-5β-androstan-17α -yl Acetate (8b)
α
Compound 6b (200 mg, 0.60 mmol) was hydrogenated and then treated with Jones reagent as given
above. Chromatography of the residue on a column (40 g of silica gel, light petroleum–ether 1 : 1)
yielded 37.6 mg (19%) of compound 7b, m.p. 159–162 °C (methanol). IR spectrum: 1 740 (C=O,
acetate); 1 716 (C=O, ketone). For C21H32O3 (332.5) calculated: 75.86% C, 9.70% H; found: 76.22% C,
9.89% H.
Continuation of the chromatography yielded 115 mg (61%) of polar compound 8b, m.p. 152–156 °C
(ref.22 gives m.p. 155–157 °C). IR spectrum: 1 737 (C=O, acetate); 1 718 (C=O, ketone). For
C21H32O3 (332.5) calculated: 75.86% C, 9.70% H; found: 76.01% C, 9.95% H.
3-Oxoandrost-4-en-17α-yl Propionate (6c)
Propionyl chloride (0.5 ml, 5.7 mmol) was added to a solution of 5 (300 mg, 1.04 mmol) in pyridine
(5 ml). After standing overnight at laboratory temperature the reaction mixture was poured into cold
water. The product was extracted with ether and the organic extract was washed with hydrochloric
acid (10%, 3 × 30 ml) and then worked up as usual. Crystallization from a mixture of acetone–
water (4 : 1) yielded 203 mg (57%) of propionate 6c, m.p. 83–86 °C (methanol), [α ]D +63 (c 2.3).
IR spectrum: 1 738 (C=O, propionate); 1 678 (C=O, ketone); 1 615 (C=C). For C22H32O3 (344,5)
calculated: 76.70% C, 9.36% H; found: 76.03% C, 9.22% H.
3-Oxo-5α-androstan-17α-yl Propionate (7c) and 3-Oxo-5β-androstan-17α-yl Propionate (8c)
Compound 6c (120 mg, 0.35 mmol) was hydrogenated and then treated with Jones reagent as given
above. PLC of the residue (light petroleum–ether 7 : 3, double elution) yielded 28 mg (23%) of lipo-
philic compound 7c, m.p. 64–67 °C (aqueous ethanol), [α]D +3 (c 0.63). IR spectrum: 1 731 (C=O,
propionate); 1 718 (C=O, ketone). For C22H34O3 (346.5) calculated: 76.26% C, 9.89% H; found:
76.01% C, 9.54% H.
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1539
Working up of PLC plates with polar compound afforded 82 mg (68 %) of oily compound 8c,
[α]D +0.6 (c 0.21). IR spectrum: 1 735 (C=O, propionate); 1 718 (C=O, ketone). For C22H34O3
(346.5) calculated: 76.26% C, 9.89% H; found: 76.41% C, 10.05% H.
3-Oxoandrost-4-en-17α-yl Butyrate (6d)
Butyryl chloride (0.5 ml, 4.81 mmol) was added to the solution of 5 (400 mg, 1.39 mmol) in pyridine
(16 ml). After 6 h at laboratory temperature the reaction mixture was poured into cold water. The
product was extracted with chloroform and the organic extract was washed with water and hydro-
chloric acid (10%, 4 × 20 ml) and then worked up as usual. Crystallization from ethanol–water (98 : 2)
yielded 272 mg (55%) of butyrate 6d, m.p. 107.5–109 °C (ethanol), [α]D +58 (c 2.41). IR spectrum:
1 732 (C=O, butyrate); 1 678 (C=O, ketone); 1 619 (C=C). For C23H34O3 (358.5) calculated: 77.05% C,
9.56% H; found: 76.53% C, 9.20% H.
3-Oxo-5α-androstan-17α-yl Butyrate (7d) and 3-Oxo-5β-androstan-17α-yl Butyrate (8d)
Compound 6d (90 mg, 0.25 mmol) was hydrogenated and then treated with Jones reagent as given
above. PLC of 85 mg of the residue (light petroleum–ether 1 : 1) yielded 14.1 mg (16%) of oily
compound 7d, [α]D +29 (c 0.49). IR spectrum: 1 732 (C=O, butyrate); 1 717 (C=O, ketone). For
C23H36O3 (360.5) calculated: 76.62% C, 10.06% H; found: 76.91% C, 9.91% H.
Working up of PLC plates of the foregoing paragraph afforded 68.5 mg (67%) of compound 8d,
[α]D +19 (c 0.74). IR spectrum: 1 732 (C=O, butyrate); 1 717 (C=O, ketone). For C23H36O3 (360.5)
calculated: 76.62% C, 10.06% H; found: 76.84% C, 9.81% H.
3-Oxoandrost-4-en-17α-yl Heptanoate (6e)
Heptanoyl chloride (0.70 ml, 4.5 mmol) was added to a solution of 5 (400 mg, 1.39 mmol) in py-
ridine (16 ml). After standing overnight at laboratory temperature the reaction mixture was poured on
ice. The product was extracted with ether and the organic extract was washed with water and hydro-
chloric acid (10%) and then worked up as usual. PLC of the residue (390 mg) on 10 plates (light
petroleum–ether 1 : 1) afforded 295 mg (53%) of oily heptanoate 6e, [α]D +45 (c 2.64). IR spectrum:
1 732 (C=O, heptanoate); 1 678 (C=O, ketone); 1 619 (C=C). For C26H40O3 (400.6) calculated:
77.95% C, 10.06% H; found: 77.63% C, 10.20% H.
3-Oxo-5α-androstan-17α-yl Heptanoate (7e) and 3-Oxo-5β-androstan-17α-yl Heptanoate (8e)
Compound 6e (300 mg, 0.75 mmol) was hydrogenated and then treated with Jones reagent as given above.
The residue (312 mg) was chromatographed on a column (50 g) of silica gel (light petroleum–ether
7 : 3). Working up of the fraction with less polar product afforded 220 mg (73%) of lipophilic com-
pound 8e, [α]D +7.0 (c 2.34). IR spectrum: 1 732 (C=O, heptanoate); 1 717 (C=O, ketone). For
C26H42O3 (402.6) calculated: 77.56% C, 10.51% H; found: 77.85% C, 10.72% H.
Continuation of chromatography afforded 40 mg (13%) of more polar product – oily compound 7e,
[α]D +11.5 (c 1.96). IR spectrum: 1 732 (C=O, heptanoate); 1 716 (C=O, ketone). For C26H42O3
(402.6) calculated: 77.56% C, 10.51% H; found: 77.01% C, 10.82% H.
3-Oxoandrost-4-en-17α-yl Decanoate (6f)
Decanoyl chloride (1.0 ml, 4.82 mmol) was added to a solution of 5 (400 mg, 1.39 mmol) in pyridine
(8 ml). After standing overnight at laboratory temperature the reaction mixture was poured on ice.
The product was extracted with ether, and the organic extract was washed with water and hydro-
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Sidova, Stransky, Kasal, Slavikova, Kohout:
chloric acid (10%) and then worked up as usual. Chromatography of the residue (862 mg) on the
column of silica gel (50 g, light petroleum–ether 7 : 3) afforded 562 mg (91%) of 6f, m.p. 52–53 °C,
[α]D +62 (c 2.46). IR spectrum: 1 731 (C=O, decanoate); 1 677 (C=O, ketone); 1 617 (C=C). For
C29H46O3 (442.6) calculated: 78.68% C, 10.47% H; found: 78.63% C, 10.20% H.
3-Oxo-5α-androstan-17α-yl Decanoate (7f) and 3-Oxo-5β-androstan-17α-yl Decanoate (8f)
Compound 6f (200 mg, 0.45 mmol) was hydrogenated as given above and then treated with Jones
reagent. The reaction mixture was worked up as usual. PLC of the residue (light petroleum–ether 7 : 3)
yielded 28 mg (14%) of oily more polar decanoate 7f, [α]D –11 (c 1.23). IR spectrum: 1 732 (C=O,
decanoate); 1 717 (C=O, ketone). For C29H48O3 (444.7) calculated: 78.33% C, 10.88% H; found:
78.01% C, 10.98% H.
Working up of PLC plates with less polar compound afforded 163 mg (82%) of oily decanoate 8f,
[α]D +3 (c 2.43). IR spectrum: 1 733 (C=O, decanoate); 1 716 (C=O, ketone). For C29H48O3 (444.7)
calculated: 78.33% C, 10.88% H; found: 78.54% C, 10.45% H.
3-Oxoandrost-4-en-17α-yl Dodecanoate (6g)
Dodecanoyl chloride (1.00 ml, 4.32 mmol) was added to a solution of 5 (400 mg, 1.39 mmol) in
pyridine (8 ml). After standing overnight at laboratory temperature the reaction mixture was poured
on ice. The product was extracted with ether, and the organic extract was washed with water and
hydrochloric acid (10%) and then worked up as usual. Crystallization from methanol–water (8 : 2)
yielded dodecanoate 6g (583 mg, 89%), m.p. 59.5–60.5 °C, [α]D +56 (c 3.22). IR spectrum: 1 731
(C=O, dodecanoate); 1 678 (C=O, ketone); 1 619 (C=C). For C31H50O3 (470.7) calculated: 79.10% C,
10.71% H; found: 78.93% C, 10.90% H.
3-Oxo-5α-androstan-17α-yl Dodecanoate (7g) and 3-Oxo-5β-androstan-17α-yl Dodecanoate (8g)
Compound 6g (130 mg, 0.28 mmol) was hydrogenated as given above and then treated with Jones
reagent. The reaction mixture was worked up as usual. PLC of the residue (light petroleum–ether 4 : 1)
yielded 9.5 mg (7%) of polar dodecanoate 7g, m.p. 59–63 °C (aqueous ethanol), [α]D +3 (c 0.65). IR
spectrum: 1 731 (C=O, dodecanoate); 1 717 (C=O, ketone). For C31H52O3 (472.8) calculated: 78.76% C,
11.09% H; found: 78.92% C, 10.94% H.
Working up of the PLC plates with lipophilic compound afforded 111 mg (85%) of the dodeca-
noate 8g, [α]D +0.3 (c 1.43). IR spectrum: 1 732 (C=O, dodecanoate); 1 717 (C=O, ketone); 1 168
(C–O). For C31H52O3 (472.8) calculated: 78.76% C, 11.09% H; found: 78.54% C, 11.41% H.
3-Oxoandrost-4-en-17α-yl Tetradecanoate (6h)
Tetradecanoyl chloride (1.00 ml, 3.73 mmol) was added to a solution of 5 (300 mg, 1.04 mmol) in
pyridine (8 ml). After standing overnight at laboratory temperature the reaction mixture was poured
on ice. The product was extracted with ether, and the organic extract was washed with water and
hydrochloric acid (10%) and worked up as usual. Crystallization from a mixture of methanol–water
(9 : 1) yielded product 6h (416 mg, 80%), m.p. 61.5–63.5 °C, [α]D +45.5 (c 2.86). IR spectrum: 1 731
(C=O, tetradecanoate); 1 677 (C=O, ketone); 1 619 (C=C). For C33H54O3 (498.8) calculated: 79.46% C,
10.91% H; found: 79.22% C, 10.52% H.
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On Steroids
1541
3-Oxo-5α-androstan-17α-yl Tetradecanoate (7h) and 3-Oxo-5β-androstan-17α-yl Tetradecanoate (8h)
Compound 6h (150 mg, 0.30 mmol) was hydrogenated as given above and then treated with Jones
reagent. The reaction mixture was worked up as usual. PLC of 140 mg of the residue (light petro-
leum–ether 3 : 2) yielded 14 mg (9%) of the tetradecanoate 7h, m.p. 51–55 °C (aqueous ethanol),
[α]D +4.5 (c 1.13). IR spectrum: 1 731 (C=O, tetradecanoate); 1 717 (C=O, ketone). For C33H56O3
(500.8) calculated: 79.14% C, 11.27% H; found: 79.48% C, 11.55% H.
Working up of PLC with the second compound afforded 116 mg (77%) of the tetradecanoate 8h,
m.p. 37–40 °C (aqueous ethanol), [α]D +2 (c 1.22). IR spectrum: 1 717 (C=O, tetradecanoate); 1 714
(C=O, ketone). For C33H56O3 (500.8) calculated: 79.14% C, 11.27% H; found: 79.01% C, 11.48% H.
3-Oxoandrost-4-en-17α-yl Octadecanoate (6i)
Octadecanoyl chloride (885 mg, 2.8 mmol) was added to a solution of 5 (300 mg, 1.04 mmol) in
pyridine (9 ml). After standing overnight at laboratory temperature the reaction mixture was poured
into cold water. The product was extracted with ether and the organic extract was washed with water
and hydrochloric acid (10%) and then worked up as usual. Chromatography of the residue (450 mg)
on the column of silica gel (100 g, benzene–ether 97 : 3) afforded 410 mg (71%) of the octadeca-
noate 6i, m.p. 85–85.5 °C (acetone), [α]D +69.5 (c 1.21). IR spectrum: 1 733 (C=O, octadecanoate);
1 679 (C=O, ketone); 1 619 (C=C). For C37H62O3 (554.9) calculated: 80.09% C, 11.26% H; found:
79.90% C, 11.45% H.
3-Oxo-5α-androstan-17α-yl Octadecanoate (7i) and 3-Oxo-5β-androstan-17α-yl Octadecanoate (8i)
Compound 6i (108 mg, 0.19 mmol) was hydrogenated as given above and then treated with Jones
reagent. The reaction mixture was worked up as usual. PLC of 105 mg of the residue (light petro-
leum–ether 7 : 3) yielded 9.5 mg (9%) of the octadecanoate 7i, m.p. 64–66 °C (acetone–heptane). IR
spectrum: 1 731 (C=O, octadecanoate); 1 718 (C=O, ketone); 1 173, 1 029 (C–O). For C37H64O3
(556.9) calculated:: 79.51% C, 11.90% H; found: 80.01% C, 11.65% H.
Working up of PLC plates with polar compound afforded 84 mg (78%) of the octadecanoate 8i,
m.p. 58–60 °C (acetone–heptane). IR spectrum: 1 732 (C=O, stearate); 1 718 (C=O, ketone); 1 169,
1 023 (C–O). For C37H64O3 (556.9) calculated: 79.51% C, 11.90% H; found: 79.98% C, 11.31% H.
The authors are indebted to Dr P. Fiedler for interpretation of IR spectra measured by Mrs K. Matouskova
1H NMR spectra were recorded by Mrs M. Snopkova. Mass spectra were measured by Dr J. Kohoutova.
The technical assistance of Dr I. Paulova and Mr M. Sisa is gratefully acknowledged. This work was
supported in part by grant No. 203/95/1309 of the Grant Agency of the Czech Republic and the Grant
ME-081 (1997) of the Ministry of Education, Youth and Sport.
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