Alkaloids of Thalictrum XXX. Eleven Minor Alkaloids From Thalictrum rugosum

Abstract

JACK L. BEAL and RAYIIOSD IT. DOSKOTCH Di; isioii q i Piinriizocog~!os~ mid A\7atiirol Prodzlcts Cheviistr?., College of Pharniacy, The Ohio Stete L-ni;,ersitj, Coliimbics, Ohio 43210.IssTR.~cr.-.ldditional alkaloids were obtained from T . ri(gosiim and characterized by spectral methods. These minor constituents were obtained from the tertiary alkaloid fractions by extensive chromatograph>-. The ether-soluble nonphenolic fraction gave ozJ-berberine ( l ) , thalriigosinone ( 2 ) , thalicthuberine 13), obaberine (l), protopine i s ) and neothalibrine (6). The ether-soluble phenolic fraction afforded aromoline ( 8 ) and coryalline 19) : while the chloroform-soluble fraction yielded rugosinone norosl-hrdrastinine (12 I and 1,2-dih~-dro-G,T-n~etli~-lenedioz~--l-osoisoq~iinoline 113 1. .111 a& i e a alkaloids for the source, x i t h thalriigosinone i2), rugosinone (10) and I,?dih:-dro-A,T-meth?-lenedios\--l-osoisoqi~inoline 113) also new natural products. -4nt1microbial activity is reported for nine alkaloids and one derivative.-4s part of a detailed study of tlie alkaloids from the genus TIzalictrztm! T . rzigoszim Xit. ( T . glamzinz Desf.) investigated in our laboratory has yielded over 20 alkaloids (see reference 1 and others therein) to whjcli we n-ish to add, in this report. eleven others present in minor amounts. They It-ere isolated from fractions which previously gave the major constituents for which details of isolation and structure elucidation are published (l).3The ether-soluble tertiary nonplienolic alkaloid fraction afforded in the order of elution from the silica gel column the following six compounds : oxyberberine (l), thalrugosinone (2): thalicthuberine (3), obaberine (4), protopine ( 5 ) and neothalibrine (6). Of these! all but tlialicthuberine (3) and neothalibrine are n-ell-characterized knon-n compounds. Sone have been reported, previously, from T . rzigoszim, and all n-ere identified from their physical and spectral properties on direct comparison with authentic samples or from values reported in tlie literature. Seothalibrine (6), a recently characterized nen-alkaloid from the fruit of T . re.ilolzitztm was identified by direct comparison It-ith tlie known compound (2j.Thalrugosinone (2) is a new bisbenzylisoquinoline alkaloid, representing a first example of a variation not previously encountered, in u-hich both tlie benzylic carbons are oxidized to the level of a ketone while the hetero ring of the isoquinoline system remains fully reduced. The limited quantities of material prevented a chemical characterization, but the apectral data is consistent n-ith a unique structure. The high resolution mass spectrum showed an intense niolecular ion that on accurate m a s measurement is in excellent agreement with the formula C3sH38S209. Its intensity supports the presence of two diphenyl ether groups (3), and the nmr spectrum clearly revealed peaks for one S-methyl and five 0-methyls. Of the four remaining oxygens, tn-o as stated are diphenyl ethers, and the other two must be carbonyls, since tlie mol...

Thalprzewalskiinone, a New Oxobenzylisoquinoline Alkaloid from Thalictrum przewalskii

“…These spectral data suggested of a quaternary oxobenzylisoquinoline alkaloid, very similar in structure to gandharamine ( 4 ), but bearing an additional methoxy group in the benzyl portion of the molecule. Furthermore, the data were also compatible with a structure quite similar to N -methylpapaveraldine ( 5 ) (prepared by the treatment of papaveraldine with methyl iodide), where one of the two benzyl-ring methoxy groups had been replaced by a phenolic hydroxy group. The mass spectral fragment ion at m / z 204 ( 2 ) was consistent with the placement of two methoxy groups in the isoquinoline portion of the molecule, while the fragment ion at m / z 151 ( 3 ) was similarly consistent with the placement of one methoxy group plus one phenolic hydroxy group in the benzyl portion of the alkaloid. − The UV spectral data tentatively supported the placement of the phenolic hydroxy group at the C-4‘ position because of the characteristic bathochromic shift in alkali that occurs when a phenolic hydroxy group is para to a carbonyl function .…”

Discovery of thalicthuberine as a novel antimitotic agent from nature that disrupts microtubule dynamics and induces apoptosis in prostate cancer cells

“… 16 TH was shown to have antimicrobial activity, especially toward Mycobacterium smegmatis and Candida albicans. 13 Here, we provide evidence that this compound arrests malignant human cell lines in mitosis and induces cell death with a mechanism of action that is distinct from classic MT inhibitors. This is the first time that such an activity has been described for TH.…”

“…Here, we present the mechanism of action study of thalicthuberine (TH), a natural product isolated from the Australian endemic tree Hernandia albiflora (Hernandiaceae). TH is a phenanthrene alkaloid with a 1-(2-aminoethyl) side chain, and was previously isolated from a wide range of plants, including Thalictrum thunbergii , 11 Thalictrum simplex , 12 Thalictrum rugosum , 13 Thalictrum delavayi , 14 Platycapnos spicata , 15 and Platycapnos sp. 16 TH was shown to have antimicrobial activity, especially toward Mycobacterium smegmatis and Candida albicans.…”

A New Alkaloid fromCorydalis hendersonii

“…1), 9-methyldecumbenine C (6), together with nine known compounds was isolated from the whole plants of C. hendersonii. The known compounds were identified as stylopine (1) [8], protopine (2) [9], canadine (3) [10], scoulerine (4) [11], tetrahydrothalifendine (5) [12], tetrahydroberberrubine (7) [13], cryptopine (8) [9], α-allocryptopine (9) [9] and 6,7-methylenedioxy-1(2H)-isoquinolinone (10) [14]. All compounds except for 1 and 2 were isolated from this plant for the first time.…”