D. J. CRAM,0. THEANDER, H
1430
JAGER A N D
11. K. STANFIELD
Tol. s5
concentrated. This crude oily dialdehyde \vas immediately on 10 g. of Alcoa alkaline alumina. The fractions eluted with dissolved in 35 nil. of benzene, about 15 tng. of anhydrous crystalbenzene (0.142 g.) were combined and crystallized from petroleum line piperidine hydroacetate was added, and the mixture was Successive ether to give 0.113 g. (76% yield), m.p. 173-177'. stirred a t room temperature for 1 hr. Ether \vas added, and the recrystallizations from acetone-petroleum ether, acetonesolution was \vashed $1 ith water, saturatctl brine, dilute acetic methanol, and twice from petroleum ether gave colorless prisms, acid, saturated sodium bicarbonate solution, again with brine 250 m r ( e 31,700). m.p. 181-183', X",:::p and finally dried over anhydrous sodium sulfate. The residue Anal. Calcd. for C ~ ~ H U O A C,: 83.25; H, 7.70. Found: obtained on evaporation of the solvent under reduced pressure C, 83.2; H , 7.7. was chromatographed on 15 g. of Florisil. The fractions eluted 3a-Acetoxy-1 lp-hydro~y-h~~-5p-androstene-18,20-dialdehydewith 301 ether in benzene through ether amounted to 25 ing. of 11fi,18-Lactol Methyl Ether (XXXVI).-Chamber B of the Rubin glassy material which crystallized on trituration with ether t o ozonolysis apparatus38 was charged with 8 ml. of methylene give 18.7 mg. of colorless crystals, i1i.p. 202-201", after sintering dichloride, the apparatus was then cooled in a Dry Ice-acetonea t 190"; 238-239 rnp ( E 9,600);",:?:A 3.1-3.15 p (aldebath, and ozone was admitted until the solvent was saturated. hyde C-HI, 5.85 (acetate C=O), 5.95 (unsaturated aldehyde Chamber X of the apparatus was then charged with a solution of C=O). On slow crystallization froin ether tlie substance was 100 mg. of the diolefin XXXY, m.p. 173-177', prepared as deobtained as colorless needles having the same melting point. scribed directly above, in l ml. of methylene dichloride and 8 ml. A m i . Calcd. for C?3H3?0;: CH30, 7.99. Found: CH.C=O 1 7 1 G ( ~ h ) Imide ~ or amide >C=O 1 6 8 4 ( ~ h )Amide ~ >C=O 11369(b)~ Lactam or acid >C=O 1 6 3 O ( ~ h ) Amide ~ band 1019(sh)d >C=C< Amide band Amide band .. .. Amide band l507(shj 1484 Thiazole skeletal vibration C H I and/or C H s 0 .. CH, and/or CH30 1437 Thiazole ring or allylic methylene 1390 Carboxyl or NHz group
.. .. 1330
CHz Thiazole ring
,.
1287(shId N H 1273 Carboxyl group 1255(sh)d Carboxyl group
125 3 1235 1215
11.58 1123 107.5 1053 1007 995 975(slij Y60(sh)d
1205(sh) 119.5'\ 1170 1125
..
1205
Carboxyl group
, .
1170 11O.j
Ether group hlonosubstd. thiazole ring
.. 1040
1000 985(shj 9.57
913 875(~h)~
941 930 YIO(sh)d
8Rd 830(~h)~ 82.5(shId 808 815 73.5 .. 72.i 707 702 694 (i90
Vinyl hydrogen
990
930 882 8.5.5 820
823
720
77: 735
4-Substd. thiazole Vinyl hydrogen 4-Substd. thiazole 4-Substd. thiazole
(i70 a The spectra of althiomycin, acetylalthiornycin and 4-methoxyAa-pyrrolin-2-one were taken on a Beckman IR-4 spectrophotometer with lithium fluoride optics in KBr disks in the region from 2500 to 4000 cm.-L. The total spectrum of thiazole-4carboxylic acid and t h e remaining spectra of the other three compounds were taken in KBr disks on a Perkin-Elmer spectrophotometer, model 21, with sodium chloride optics. Spectra taken on the polymorph which crystallized as plates. Broad band which spans the wave numbers indicated. sh = shoulder. e b = broad.
derivative that occur in this region could also be associated with a 4-substituted thiazole ring. The same could be said of the multitude of bands exhibited by the althiomycin and its acetyl derivative a t 930-800 tin.-*, since all 4monosubstituted thiazoles t h a t have been
STRUCTURE OF ALTHIOMYCIN
May 20, 1963
1433
TABLE I11 NUCLEARMAGNETIC RESONANCE DATAFOR ALTHIOMYCIN AND Compound
Solvent
4-Methoxy-A3-pyrrolin-2-onea
CDClaI
Thiazole-4-carboxylic acidb
(CDa)zSO
I
6.20 6.08 4.93 1.60 0.92 0.45 7.75 -6.3 6.10 5.67 4.83 4.56 3.63 2.24
i
CDC18
Acetylalthiomycin”
ITS
DEGRADATION PRODUCTS
Peak multiplicity
r
Singlet Singlet Singlet )Partially resolved doublets Singlet Singlet Multiplet Singlet Singlet Singlet Singlet Triplet Singlet
1
No. H’s
3 2 1 1 1 1 3 2 3 2 1
1 1 1
Possible assignment
CHsO N-CHI C=C-H Aromatic H’s CO?H CHaCO CHz CHaO CHz C=C-H C=C-H
0
II
H-C--N Aromatic H’s
i
1 (Unresolved) 1 doublets ArCH=N1 Singlet 13 Unresolved multiplet Singlet ? 6.55 13.9 5 Unsymmetrical 6.13 Althiomycin Singlet? 1.8 5.68 Singlet lC 4.62 Singlet lC 3.87 Triplet? 2.4 Unresolved 1.67 Doublet? 2 6.54 CHz Doublet-doublet Cysteine CF~CO~H~ CH 1 5.22 Quadruplet b Taken on a Varian Associates V-4300 a Taken on Varian associates A-60, analytical n.m.r. spectrophotometer at 60 megacycles. high resolution n.m.r. spectrophotometer a t 40 megacycles. The relative areas under the peaks were estimated using a planimeter. The number of hydrogens were approximated by a planimeter and the smallest peak ( 4.62) was assumed to have an area equivalent to one proton. The multiplicity of the signal is such that the doublet due to the methylene group adjacent to the a-hydrogen is further group attached to the same carbon atom. These split by the sulfide hydrogen. The a-hydrogen signal appears to be split by the D. data arid interpretation are taken from F. A. Bovey and G. V. D. Tiers, J . A m . Chem. SOC.,81, 2870 (1959), and 0. Jardetyky and Jardetyky, J . ,3201. Chem., 233, 383 (1958). 1.55 1.41 0.00 7.50
i
c.
examineds usually showed two to four bands a t these wave lengths. The infrared spectral comparisons offer no direct evidence for the presence of the 4-methoxy-A3-pyrrol2-one ring system in althiomycin or acetylalthiomycin. However, the band by which this ring system would be attached t o the larger molecules is hydrolytically very labile, a fact which suggest that the conjugated system of the pyrrolone might be extended in the larger molecules, and therefore modified spectroscopically. All three molecules contain a number of strong bands in the double bond region attributable to amide, imide or lactam absorptions. The band in acetylalthiomycin a t 1780 cm.-’ deserves special comment. Relatively few groups absorb a t this high a frequency: @-lactams, oxazolones and five-membered cyclic imides.7b Since oxazolones are formed in the medium used to convert althiomycin to acetylalthiomycin, the band a t 1780 ern.-' in acetylalthiomycin might be due to this ring system (VII). 0 / \ CH3-7,
the spectrum of acetylalthiomycin, 17 hydrogens are accounted for of the 17-19 suggested by the empirical formula. Unfortunately, the spectrum of althiomycin was not integrated, and was too poor to allow any meaningful quentitative estimates to be made. The compound decomposes slowly in dimethyl sulfoxide and is insoluble in the usual solvents used in n.m.r. spectral measurements. The spectrum of the pyrrolone is distinct, and gives the expected three sharp singlets with areas in the ratio of 3 : 2: 1, which correspond to the methoxyl, methylene and vinyl hydrogens, respectively. These three singlets are clearly visible with the same relative intensity in the spectrum of acetylalthiornycin, but the three bands (7 = (3.10, 5.G7 and 4.83) are shifted to lower 7-values by 0.1 to 0.4 7 unit. These lower values reflect lower shielding of the hydrogens in the pyrrolone ring system attached to the larger molecule than in the simple heterocycle, an effect to be expected from a part
,C=O
N-CH I CHz-SVI1
Nuclear Magnetic Resonance Spectra.-Table I11 contains the nuclear magnetic resonance spectra of althiomycin, 9 acetylalthiomycin, 4-methyl-A3-pyrrol2-one] thiazole-4-carboxylic acid and cysteine. In (9) The authors are indebted to Drs. I,. F. Johnson and D. P. Hollis of Varian Associates for these spectra.
II
,k=o
,c--0
1
I
VI11
structure such as VIII. The carbonyl group attached to nitrogen in VI11 withdraws electrons from nitrogen, and decreases the shielding for the ring system, particularly for the methylene group attached to nitrogen (which shows the greatest decrease in 7-value). The
D. J. CRAM, 0. THEANDER, H. JAGER
1434
same three peaks are found in althiomycin itself at about the same 7-values as in acetylalthiomycin. The two ring hydrogens of thiazole-4-carboxylic acid absorb a t T = 1.60(--N=CH-S-) and 0.92 (-SCH=C
