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Michelle L. BRAY, Daniela GORBACHEVA, Hossain JAHANSOUZ, Michael J. KA ...
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
1-4
Published: 2001
Released on J-STAGE: March 29, 2002
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The degradation of [5S-[5α, 6β, 7α(R
*)]]-2-butyl-5-(1, 3-benzodioxol-5-yl)-7-[(2-carboxypropyl)-4-methoxy-phenyl]-6-dihydro-5H-cyclopenta[b]pyridine-6-carboxylic acid (J-104, 132) was studied in aqueous solution as a function of temperature and pH. The degradation reaction does not proceed to completion; rather, a stable equilibrium is attained in which approximately 2% of the degradate is produced. Kinetic data for the formation of the degradate are analyzed using an integrated form of the rate law for a reversible first-order reaction, and the forward and reverse rate constants and overall equilibrium constants are presented. Isolation and spectroscopic structural determination indicate that the degradate is the C7 β-epimer of the drug. A mechanism for the epimerization reaction involving a novel enamine-like intermediate is proposed and shown to be consistent with the kinetic data. The rate and equilibrium constants are used to predict the room temperature stability of an injectable formulation of J-104, 132, and these predictions are compared to actual data from long-term stability studies. It is concluded that the preformulation kinetic studies provide essential data needed for optimum drug product development.
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Hideko KAWAKI
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
5-9
Published: 2001
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Thermodynamic parameters were determined by variable temperature experiments on the gas liquid chromatography (GLC) relative retention values, log γ, of 3- and 4-substituted halogenobenzene derivatives under non-polar condition. These ΔΔH
Sº(R, X) had a compensational relation with the ΔΔS
Sº(R, X) values. The free energy change ΔΔG
Sº(R, X) which is estimated from the ΔΔH
Sº(R, X) and the ΔΔS
Sº(R, X) at 298 K is less than −23 kJ·mol
-1. The ΔΔS
Sº(R) values could be explained by translational entropy change for the adsorbed active complex between the solute and stationary phase. It is suggested that the interaction could be mainly expressed by the physical adsorption exclusive of hydrogen bonding. The ΔΔG
Sº(R, X) values for each halogen derivative have been the excellent linear lines taking the same slopes for the monosubstituted benzene derivatives, ΔΔG
Sº(R). The regression analyses of their intercepts were given using the descriptor evaluated as the molecular volume σ
a(X) rather than σ
M(X). The regression analysis for polyhalogenobenzene was also given successfully using σ
a(X
n).
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Adriano D. ANDRICOPULO, Rosendo A. YUNES
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
10-17
Published: 2001
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Values of inhibition constants, K
i, and concentrations required for 50% inhibition, IC
50, for a collection of structurally diverse competitive inhibitors of calf spleen purine nucleoside phosphorylase have been determined employing inosine as substrate. These values have been employed to create predictive quantitative structure-activity relationships (QSAR) which link structure to values of K
i and IC
50. These QSAR models have substantial power to predict values and the associated uncertainties for K
i and IC
50 for unknown, structurally diverse inhibitors of purine nucleoside phosphorylase.
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Mitsuru SATOH, Naoki TAKEUCHI, Takeshi NISHIMURA, Takashi OHTA, Seisho ...
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
18-22
Published: 2001
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11-Chloro-3-methoxy-2-undecenal was synthesized from 8-bromooctanol, and an annelation reaction with this aldehyde and ethyl acetoacetate proceeded to give the ethyl 6-(8-chlorooctyl)salicylate. Ethyl 6-(8-chlorooctyl)salicylate was converted to ethyl 6-(7-formylheptyl)-2-methoxybenzoate through the iodide after protection of the phenolic hydroxyl group. Finally, the Wittig reaction with the aldehyde and triphenylphosphonium iodides in the presence of BuLi gave the methoxybenzoates, and then treatments of these methoxybenzoates with BBr
3 in CH
2Cl
2 and 10% NaOH in ethanol gave 6-[8(Z), 11(Z)-pentadecadienyl]salicylic acid (anacardic acid 3) and 6-[8(Z), 11(Z), 14-pentadecatrienyl]salicylic acid (anacardic acid 4) which were isolated from plants of the anacardiaceae.
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Takanobu SHIMIZU, Akihiko TOBARI, Jyunichi KOYANAGI, Masami KAWASE, Se ...
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
23-28
Published: 2001
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Bromination of 17-O-acetyltestosterone (17β-acetoxyandrost-4-en-3-one) (1) was performed with 1, 5, and 10 eq of Br
2 in AcOH-Et
2O at room temperature. In all cases 2α, 6β- (2) and 2α, 6α-dibromo-17β-acetoxyandrost-4-en-3-one (3) were obtained, although the yields were dependent upon the conditions used. Bromination of compound 1 with 10 eq of Br
2 in the presence of silver trifluoromethanesulfonate (silver triflate, AgOTf) at room temperature for 12 h gave 2, 7α-dibromo- (4) and 2, 4, 7α-tribromo-17β-acetoxy-3-hydroxy-1-methylestra-1, 3, 5(10)-triene-6-one (5). The formations of the products were inferred on the basis of products obtained under controlled brominations of 1 in the presence of AgOTf, and of those obtained by the brominations of compounds 9-13 also in the presence of AgOTf.
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Masaji SUZUKI, Yutaka OHUCHI, Hajime ASANUMA, Toshie KANEKO, Sadakazu ...
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
29-39
Published: 2001
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A series of 8'-substituted N-(endo-8-azabicyclo[3.2.1]oct-3-yl)-1-isopropyl-2-oxo-1, 2-dihydro-3-quinolinecarboxamides were synthesized. The 5-HT
4 receptor agonistic activity was evaluated using the isolated guinea pig ileum preparation. Of the compounds synthesized, N-(endo-8-(3-hydroxypropyl)-8-azabicyclo[3.2.1]oct-3-yl)-1-isopropyl-2-oxo-1, 2-dihydro-3-quinolinecarboxamide (15a, TS-951) exhibited the most potent serotonin 5-HT
4 receptor agonistic activity. This compound had a high affinity for the serotonin 5-HT
4 receptor althought it had no affinities for other broad spectrum receptors. Furthermore, it remarkably enhanced gastrointestinal motility in conscious fed dogs without unfavorable effects that non-selective serotonin 5-HT
4 receptor agonist has. TS-951 may be useful in improving gastrointestinal dysfunction.
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Masayuki HARAMURA, Akira OKAMACHI, Kouichi TSUZUKI, Kenji YOGO, Makoto ...
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
40-43
Published: 2001
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Motilin antagonist was designed and synthesized on the basis of the structure-activity relationship analysis of porcine motilin that we reported recently. The drug design was performed on a specific concept to reduce a flexibility of peptide conformation of porcine motilin partial peptide by its cyclization. The cyclic peptide was synthesized using Boc (tert-butyloxycarbonyl) solid phase methodology, followed by cyclization using the azide procedure, and tested for the binding activity to motilin receptor and smooth muscle contractile activity. The cyclic peptides 3, 4, and 5 showed antagonistic property on contraction assay (pA
2 [the negative logarithm of molar concentration of antagonist causing a 2-hold shift to the right of the concentration-response curve for motilin]: 4.5, 4.34, and 4.04, respectively, in rabbit duodenum) and no contractile activity even at high concentration.
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Kazumi HIRATA, Jyunko ARAYA, Shiro NAKAIKE, Kunihiro KITAMURA, Toshima ...
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
44-48
Published: 2001
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NCA0424 (1) and its side chain positional isomer, NCA0465 (2), are indoloquinoxaline derivatives with potent antitumor activity. To investigate the effect of side chain position for binding with DNA, the interactions of 2 with various B-form DNAs were studied by spectroscopic (circular dichroism (CD), fluorescence and UV) and viscosity measurements and were compared with those of 1. The binding preference for the base sequence was different in each case. The CD spectra showed that 2 formed an asymmetric binding of indoloquinoxaline ring with adenine in DNA, whereas such a base selectivity was not found with 1. The binding features are discussed based on association constants and thermodynamic parameters, indicating the importance of the side chain position for binding specificity for DNA.
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Hiroko NAKAGAWA, Kanae GOMI, Koh-ichi YAMADA
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
49-53
Published: 2001
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Chiral recognition of alkyl β-D-pyranoside micelles toward [7] and [5] heterohelicenes possessing helical structures was investigated by
1H-NMR and CD (circular dichroism) spectroscopy. In dodecyl maltopyranoside micellar solution, P and M enantiomers of tetrathia[7]heterohelicene (7TH), which have rigid and stable helixes, manifested different chemical shifts in their
1H-NMR spectra due to differences in the diastereomeric interactions, implying that the micelles undergo stronger recognition toward the M enantiomer than the P enantiomer. On the other hand, in octyl glucopyranoside micellar solution, trithia[5]heterohelicene (5TH) and two kinds of its derivatives which are rapidly equilibrated between the enantiomers in solution, gave no distinctly resolved
1H-NMR peaks for either enantiomer even at a lowered temperature. However, these racemic [5]heterohelicenes in the micelles did develop induced CD absorptions owing to a displacement of the equilibrium, suggesting from the signs of their Cotton effects that the micelles prefer the M enantiomer to its antipode in conformity with the
1H-NMR results of 7TH.
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Medicinal Foodstuffs. XXI. Structures of New Cucurbitane-Type Triterpene Glycosides, Goyaglycosides-a, -b, -c, -d, -e, -f, -g, and -h, and New Oleanane-Type Triterpene Saponins, Goyasaponins I, II, and III, from the Fresh Fruit of Japanese Momordica charantia L.
Toshiyuki MURAKAMI, Akihito EMOTO, Hisashi MATSUDA, Masayuki YOSHIKAWA
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
54-63
Published: 2001
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Eight cucurbitane-type triterpene glycosides called goyaglycosides-a, -b, -c, -d, -e, -f, -g, and -h and three oleanane-type triterpene saponins termed goyasaponins, I, II, and III were isolated from the fresh fruit of Japanese Momordica charantia L. (Cucurbitaceae) together with five known cucurbitane-type triterpene glycosides momordicosides A, C, F
1, I, and K. The structures of goyaglycosides and goyasaponins were elucidated on the basis of chemical and physicochemical evidence.
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Satoru WATANO, Jyunpei FURUKAWA, Yoshifumi OSAKO, Teruhito YASUTOMO
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
64-68
Published: 2001
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In our previous paper [Watano S. et al., J. Powder Technology Japan, 37, 362-370 (2000)], a novel compaction tester was developed to quantitatively evaluate the water dispersion condition of a wet kneaded mass prepared by a paddle type kneader. It has been demonstrated that the physical properties of pellets prepared by extrusion granulation after the kneading can be well predicted by the pressure transmission obtained through the compaction tester. This paper describes a more detailed investigation of the water dispersion, its mechanism and pressure transmission characteristics of wet kneaded masses prepared under various operating conditions. First, kneading by a paddle type kneader was conducted to prepare wet masses under various binder contents using different additional methods and different starting materials. Secondly, water dispersion and pressure transmission characteristics of wet masses were investigated. After the wet kneading, the wet kneaded masses were extruded through a dome type extruder and were dried by a fluidized bed to prepare dry pellets. The relationship between water dispersion and pressure transmission can be expressed by a single line, regardless of binder content or methods of addition. This implies that these parameters have no effect on the water dispersion condition of the wet kneaded mass prepared by a high shear paddle type kneader. Different water dispersion characteristics and the mechanism obtained by different starting materials can also be evaluated by the pressure transmission data. Properties of dry pellets can also be predicted by the pressure transmission. It can be concluded that the developed compaction tester can quantitatively evaluate the water dispersion condition of a wet kneaded mass and also predict properties of the final extruded products.
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Hisashi MATSUDA, Toshio OHTA, Atsuhiro KAWAGUCHI, Masayuki YOSHIKAWA
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
69-72
Published: 2001
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Five paeonol glycosides, suffruticosides A, B, C, D, and E, and a monoterpene glucoside, galloyl-oxypaeoniflorin, were isolated from the glycosidic fraction of Chinese Moutan Cortex, the root cortex of Paeonia suffruticosa Andrews, together with paeonolide, apiopaeonoside, galloyl-paeoniflorin, oxypaeoniflorin, and paeoniflorin. The structures of five suffruticosides and galloyl-oxypaeoniflorin were elucidated on the basis of chemical and physicochemical evidence. Suffruticosides A, B, C, and D, galloyl-oxypaeoniflorin, and galloyl-paeoniflorin exhibited more potent radical scavenging effects than α-tocopherol.
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Toshiyuki MURAKAMI, Kentarou KOHNO, Hisashi MATSUDA, Masayuki YOSHIKAW ...
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
73-77
Published: 2001
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Two new oleanane-type triterpene oligoglycosides, pisumsaponins I and II, and two new kaurane-type diterpene oligoglycosides, pisumosides A and B, were isolated from the immature seeds (green peas) of Pisum sativum L. together with soyasaponin I, bersimoside I, dehydrosoyasaponin I, and their 6'-methyl esters. The structures of pisumsaponins and pisumosides were determined on the basis of chemical and physicochemical evidence as 22-O-malonylsoyasapogenol B 3-O-α-L-rhamnopyranosyl(1→2)-β-D-galactopyranosyl(1→2)-β-D-glucopyranosiduronic acid (22-O-malonylsoyasaponin I), sandosapogenol 3-O-α-L-rhamnopyranosyl(1→2)-β-D-galactopyranosyl(1→2)-β-D-glucopyranosiduronic acid, 17-O-β-D-glucopyranosyl-6β, 7β, 13β, 17-tetrahydroxy-19-kauranoic acid 19-O-β-D-glucopyranosyl(1→2)-β-D-glucopyranoside, and 6β, 7β, 13β, 17-tetrahydroxy-19-kauranoic acid 19-O-β-D-glucopyranosyl(1→2)-β-D-glucopyranoside, respectively.
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Naomi ONO, Fumitoshi HIRAYAMA, Hidetoshi ARIMA, Kaneto UEKAMA
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
78-81
Published: 2001
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The competitive inclusion complexations in the ternary phenacetin/competitors/β-cyclodextrin (β-CyD) systems were investigated by the solubility method, where m-bromobenzoic acid (m-BBA) and o-toluic acid (o-TA) were used as competitors. The solubility changes of the drug and competitors as a function of β-CyD concentration in the ternary systems were formulated using their stability constants and intrinsic solubilities. The decrease in solubility of phenacetin by the addition of competitors could be quantitatively simulated by the formulation, when both drug and competitor give A
L type solubility diagrams. On the other hand, when one of the guests gives a B
S type solubility diagram, its solubility change was clearly reflected in that of the another guest, i.e., phenacetin gave an A
L type solubility diagram in the binary phenacetin/β-CyD system and O-TA gave a B
S type diagram in the binary O-TA/β-CyD system, but in the ternary phenacetin/O-TA/β-CyD system, a new plateau region appeared in the original A
L type diagram of phenacetin. This was explained by the solubilization theory of Higuchi and Connors. The solubility analysis of the ternary drug/competitor/CyD systems may be particularly useful for determination of the stability constant of a drug whose physicochemical and spectroscopic analyses are difficult, because they can be calculated by monitoring the solubility change of a competitor, without monitoring that of a drug. Furthermore, the present results suggest that attention should be paid to the type of the phase solubility diagram, as well as the magnitude of the stability constant and the solubility of the complex, for a rational formulation design of CyD complexes.
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Masateru ONO, Megumi YAMAMOTO, Takako YANAKA, Yasuyuki ITO, Toshihiro ...
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
82-86
Published: 2001
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Ten new labdane-type diterpenes were isolated from the fruit of Vitex rotundifolia L. (Verbenaceae), along with a known diterpene, vitexilactone. Their chemical structures were determined on the bases of spectroscopic data.
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Masanori SOMEI, Fumio YAMADA, Takashi KURAUCHI, Yoshiyuki NAGAHAMA, Ma ...
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
87-96
Published: 2001
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Application of regioselective nucleophilic substitution reactions of 1-hydroxytryptamines to novel and simple syntheses of serotonin (1a), N-methylserotonin (1b), bufotenine (1c), 5-methoxy-N-methyltryptamine (2a), bufobutanoic acid (3a), N-(indol-3-yl)methyl-5-methoxy-N-methyltryptamine (4), and lespedamine (5) are described. Effective syntheses of 5-benzyloxytryptamine and 1-methoxy-2-oxindoles are also reported.
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Munetaka KUNISHIMA, Daisuke NAKATA, Takayuki SAKUMA, Kazuhiro KONO, Sh ...
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
97-100
Published: 2001
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Transformation of acetals into ethers by partial reduction using a samarium diiodide—Lewis acids—acetonitrile system is described. The reaction with aromatic acetals occurred in good yields in the presence of aluminum chloride (2 eq) whereas the corresponding aliphatic, vinylic, and alkynyl derivatives did not afford ethers under the same conditions. β-Elimination to give an enol ether becomes predominant when aliphatic acetals that possess a hydrogen at the 2-position are treated with iodotrimethylsilane in the presence of SmI
2 or SmI
3.
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Kazuya MATSUO, Youichi YAMAMOTO, Noriyuki KADO, Masahiro YAMAZAKI, Osa ...
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
101-104
Published: 2001
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The kinetics of racemization of meluadrine tartrate in aqueous solution was investigated by HPLC, over the pH range of 1.2 to 12 at 40, 60 and 80 °C. The racemization was followed by measuring both the residual (R)-enantiomer and formed (S)-enantiomer of meluadrine. The pH-racemization rate profile of meluadrine showed a minimum racemization rate constant between pH 4 and 6, and the rate constant increased rapidly with decreasing pH below pH 3. In the basic region, the racemization rate constant showed a maximum at around pH 9. Four pathways of racemization of meluadrine are proposed, depending on the dissociation state of the phenolic and amino groups. The calculated racemization rate-pH profile agreed well with the observations. The values of activation energy (95-115 kJ/mol) suggest that a similar quinoid intermediate is involved throughout the pH range examined. The objective of this study is to clarify the racemization mechanism of benzylalcohol derivative with phenoric group. This study offers fundamental knowledge for the other benzylalcohol derivatives, which have similar moiety structure.
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ATTA-UR-RAHMAN, Muhammad Iqbal CHOUDHARY, Safdar HAYAT, Abdul Majeed ...
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
105-107
Published: 2001
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Two new aurones, 4'-chloro-2-hydroxyaurone (1) and 4'-chloroaurone (2) were isolated from Spatoglossum variabile. The structures of these compounds were elucidated by modern spectroscopic techniques.
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Jung-Bum LEE, Preeprame SRISOMPORN, Kyoko HAYASHI, Tomoyasu TANAKA, Us ...
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
108-110
Published: 2001
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Calcium ion binding with the anionic part of a molecule was replaced with various metal cations and their inhibitory effects on the replication of herpes simplex virus type 1 were evaluated. Replacement of calcium ion with sodium and potassium ions maintained the antiviral activity while divalent and trivalent metal cations reduced the activity. Depolymerization of sodium spirulan with hydrogen peroxide decreased in antiviral activity as its molecular weight decreased.
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Toshiyuki KIMURA, Shechun YAO, Kazuhito WATANABE, Shigemi KONDO, Ing K ...
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
111-113
Published: 2001
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Methyl (2), ethyl (3), propyl (4), butyl (5), allyl (6), benzyl (7), o-, m-, p-xylyl (8-10), and α-phenylethyl (11) derivatives of arabinofuranosyluracil (1) were synthesized and their pharmacological effects in mice were examined by using hypnotic activity and synergism with pentobarbital as indices for the CNS depressant effects. At a dose of 2.0 μmol/mouse by intracerebroventricular injection, the values of mean sleeping time induced by 7-11 were 144, 154, 117, 33, and 34 min, respectively, whereas the alkyl (2-6) derivatives did not cause any hypnotic activity. N
3-o-Xylylarabinofuranosyluracil (8) displayed the most potent hypnotic activity among the derivatives tested. Certain derivatives (6-11) significantly prolonged the pentobarbital-induced sleeping time compared to control. The present study indicated that substitution with benzyl and/or related groups on the N
3-position of arabinofuranosyluracil produced CNS depressant effects.
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Takashi ICHIYANAGI, Kikuo OIKAWA, Chigusa TATEYAMA, Tetsuya KONISHI
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
114-117
Published: 2001
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Acid mediated hydrolysis of anthocyanins was studied using capillary zone electrophoresis (CZE). A commercially available wild blueberry (Bilberry) extract was dissolved in different concentrations of TFA (0.1, 1, 3, 9%), then was subjected to thermodecomposition reaction at 95 °C. After the reaction, the samples were analyzed by CZE. The hydrolysis rate of each anthocyanin and the formation of the aglycon were determined by the change in the peak pattern of the anthocyanins in the electropherogram. Each anthocyanin peak decreased time dependently in a first order kinetic fashion. It was revealed that the hydrolysis rate of each anthocyanin was determined primarily by the type of conjugated sugar and not by the aglycon structure. The rate constant of anthocyanin hydrolysis was in the following order, arabinoside>galactoside>glucoside without regard to the aglycon structure. The kinetic behavior of this anthocyanin hydrolysis together with the CZE mobility allowed us to identify an unknown CZE peak as delphinidin 3-O-β-arabinoside. At low TFA concentration, significant decomposition of the anthocyanidin nucleus occurred, but the glycoside hydrolysis predominated at high TFA concentration. It was further revealed that the aglycon released reacted successively to form polymeric products at higher TFA conditions.
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Tamaki MIYAZAKI, Chikako YOMOTA, Satoshi OKADA
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
118-122
Published: 2001
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Depolymerization of sodium hyaluronate (HA) by tetracyclines was investigated. Reduction in HA molecular weight was followed by size exclusion chromatography with a low angle laser light scattering detector. On mixing with oxytetracycline hydrochloride (OTC) solution and incubating at 37 °C, HA was gradually depolymerized. OTC, a representative antibiotic, is known as a photosensitizer, and phototoxic side effects relevant to radicals have been reported. However, HA depolymerization required no irradiation. As time passed, OTC solution incubated at 37 °C got colored reddish brown, even in the dark. With reversed-phase HPLC separation, several peaks derived from decomposed OTC appeared. One of the peaks had an absorbance in the visible range. A quantitative correlation between the discoloration and the HA depolymerization rate was obtained. On the other hand, when samples were incubated below 25 °C, change of color was slight, and practically no HA depolymerization was observed after up to 4 h. Oxygen depletion by nitrogen saturation or addition of mannitol also prevented the depolymerization. Under anaerobic conditions, the color of the solution did not change, whereas it turned red under aerobic conditions in the presence of mannitol. The mannitol did not inhibit the OTC decomposition, but it preserved HA from damage. On the basis of the known decomposition of OTC and the results of HPLC separation, anhydrooxytetracycline can be proposed as the derivative causing HA depolymerization.
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Shuichi TONO-OKA, Masanori HATAKEYAMA
Article type: scientific monograph
2001 Volume 49 Issue 1 Pages
123-125
Published: 2001
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Several 2-alkanols (2-propanol, 2-butanol, 2-pentanol, etc.) were examined as substrates for ADP-ribosylation in the NAD/NADase enzymatic system. Even though these secondary alcohols have hydroxy groups that are subject to the steric influence of a methyl group, they were shown to be efficiently ADP-ribosylated. However, in the case of 3-alkanol (3-butanol), only slight ADP-ribosylation was observed. In this enzymatic reaction, 1, 2-propanediol provided both 1-O- and 2-O-ADP-ribosylation products in the ratio 1:1 as determined by
1H-NMR spectrometry. On the other hand, an equimolar mixture system of 1- and 2-propanols provided major 1-O- and minor 2-O-ribosylation products in the ratio 4:1. This is the first report of O-ADP-ribosylation of terminal secondary alcohols with the NAD/NADase enzymatic system.
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