Structure fragmentation studies of ring-substituted N-trifluoroacetyl-N-benzylphenethylamines related to the NBOMe drugs.

RATIONALE: The halogenated derivatives of N-(2-methoxy)benzyl-2,5-dimethoxyphenethylamine (25-NBOMe) such as the 4-bromo analogue (25B-NBOMe) represent a new class of hallucinogenic or psychedelic drugs. The purpose of this study was to determine the role of the electron-donating groups (halogen and dimethoxy) in the pathway of decomposition for the distonic molecular radical cation in the electron ionization mass spectrometry (EI-MS) process of the trifluoroacetamide (TFA) derivatives. METHODS: The systematic removal of substituents from the 4-halogenated 2,5-dimethoxyphenethylamine portion of the N-dimethoxybenzyl NBOMe analogues allowed an evaluation of structural effects on the formation of major fragment ions in the EI-MS of the TFA derivatives. All six regioisomeric dimethoxybenzyl-substituted analogues (2,3-, 2,4-, 2,5-, 2,6-, 3,4- and 3,5-dimethoxy) for the four series of phenethyl aromatic ring substitution patterns were prepared, derivatized and analyzed via gas chromatography coupled with EI-MS. RESULTS: The analogues yield two unique radical cation fragments from the decomposition of the common distonic molecular radical cation. The substituted phenylethene radical cation (m/z 164) is the base peak or second most abundant ion in all six TFA-2,5-dimethoxyphenethylamine isomers. The dimethoxybenzyltrifloroacetamide radical cation (m/z 263) is the base peak or second most abundant ion in the 2- and 3-monomethoxyphenethylamine isomers. However, the 2- and 3-methoxyphenylethene radical cation (m/z 134) is among the five most abundant ions for each of these twelve isomers. Only one isomer in the phenethylamine series yields the corresponding unsubstituted phenylethene radical cation at m/z 104. CONCLUSIONS: The decomposition of the hydrogen-rearranged distonic molecular radical cation favors formation of the dimethoxybenzyltrifloroacetamide (m/z 263) species for the less electron-rich phenethyl aromatic rings. The addition of electron-donating groups to the aromatic ring of the phenethyl group as in the NBOMe-type molecules shifts the decomposition of the common distonic molecular radical cation to favor the formation of the electron-rich substituted phenylethene radical cation.

Slow-Binding Inhibition of Mycobacterium tuberculosis Shikimate Kinase by Manzamine Alkaloids.

Tuberculosis represents a significant public health crisis. There is an urgent need for novel molecular scaffolds against this pathogen. We screened a small library of marine-derived compounds against shikimate kinase from Mycobacterium tuberculosis ( MtSK), a promising target for antitubercular drug development. Six manzamines previously shown to be active against M. tuberculosis were characterized as MtSK inhibitors: manzamine A (1), 8-hydroxymanzamine A (2), manzamine E (3), manzamine F (4), 6-deoxymanzamine X (5), and 6-cyclohexamidomanzamine A (6). All six showed mixed noncompetitive inhibition of MtSK. The lowest KI values were obtained for 6 across all MtSK-substrate complexes. Time-dependent analyses revealed two-step, slow-binding inhibition. The behavior of 1 was typical; initial formation of an enzyme-inhibitor complex (EI) obeyed an apparent KI of ∼30 µM with forward ( k5) and reverse ( k6) rate constants for isomerization to an EI* complex of 0.18 and 0.08 min-1, respectively. In contrast, 6 showed a lower KI for the initial encounter complex (∼1.5 µM), substantially faster isomerization to EI* ( k5 = 0.91 min-1), and slower back conversion of EI* to EI ( k6 = 0.04 min-1). Thus, the overall inhibition constants, KI*, for 1 and 6 were 10 and 0.06 µM, respectively. These findings were consistent with docking predictions of a favorable binding mode and a second, less tightly bound pose for 6 at MtSK. Our results suggest that manzamines, in particular 6, constitute a new scaffold from which drug candidates with novel mechanisms of action could be designed for the treatment of tuberculosis by targeting MtSK.

Comparing the dopaminergic neurotoxic effects of benzylpiperazine and benzoylpiperazine.

Benzylpiperazine has been designated as Schedule I substance under the Controlled Substances Act by Drug Enforcement Administration. Benzylpiperazine is a piperazine derivative, elevates both dopamine and serotonin extracellular levels producing stimulatory and hallucinogenic effects, respectively, similar to methylenedioxymethamphetamine (MDMA). However, the comparative neurotoxic effects of Piperazine derivatives (benzylpiperazine and benzoylpiperazine) have not been elucidated. Here, piperazine derivatives (benzylpiperazine and benzoylpiperazine) were synthesized in our lab and the mechanisms of cellular-based neurotoxicity were elucidated in a dopaminergic human neuroblastoma cell line (SH-SY5Y). We evaluated the in vitro effects of benzylpiperazine and benzoylpiperazine on the generation of reactive oxygen species, lipid peroxidation, mitochondrial complex-I activity, catalase activity, superoxide dismutase activity, glutathione content, Bax, caspase-3, Bcl-2 and tyrosine hydroxylase expression. Benzylpiperazine and benzoylpiperazine induced oxidative stress, inhibited mitochondrial functions and stimulated apoptosis. This study provides a germinal assessment of the neurotoxic mechanisms induced by piperazine derivatives that lead to neuronal cell death.

Differentiation of cyclic tertiary amine cathinone derivatives by product ion electron ionization mass spectrometry.

RATIONALE: A number of synthetic cathinones (aminoketones, 'bath salts') are tertiary amines containing a cyclic amino group, most commonly pyrrolidine. These totally synthetic compounds can be prepared in a number of regioisomeric designer modifications and many of these can yield isomeric major fragment ions in electron ionization mass spectrometry (EI-MS). METHODS: A series of regioisomeric cyclic tertiary amines were prepared and evaluated in EI-MS and MS/MS product ion experiments. The cyclic amines azetidine, pyrrolidine, piperidine and azepane were incorporated into a series of aminoketones related to the cathinone derivative drug of abuse known as MDPV. Deuterium labeling in both the cyclic amine and alkyl side chain allowed for the confirmation of the structure for the major product ions formed from the EI-MS iminium cation base peaks. RESULTS: These iminium cation base peaks show characteristic product ion spectra which allow differentiation of the ring and side-chain portions of the structure. The small alkyl side chains favor ring fragmentation in the formation of the major product ions. The higher side-chain homologues appear to promote product ion formation by side-chain fragmentation. Both side-chain and ring fragmentation yield a mixture of product ions in the piperidine and azepane series. CONCLUSIONS: Product ion fragmentation provides useful data for differentiation of cyclic tertiary amine iminium cations from cathinone derivative drugs of abuse. Regioisomeric iminium cations of equal mass yield characteristic product ions for the alkyl side-chain homologues of azetidine, pyrrolidine, piperidine and azepane cyclic amines.

Product ion tandem mass spectrometric differentiation of regioisomeric side-chain groups in cathinone derivatives.

RATIONALE: Precursor materials are available to prepare aminoketone drugs containing regioisomeric propyl and isopropyl side-chain groups related to the drug alpha-pyrrovalerone (Flakka) and MDPV (3,4-methylenedioxypyrrovalerone). These compounds yield equivalent regioisomeric iminium cation base peaks in electron ionization mass spectrometry (EI-MS). METHODS: The propyl and isopropyl side-chain groups related to alpha-pyrrovalerone and MDPV were prepared and evaluated in EI-MS and tandem mass spectrometry (MS/MS) product ion experiments. Deuterium labeling in both the pyrrolidine and alkyl side-chain groups allowed for the confirmation of the structures for the major product ions formed from the regioisomeric EI-MS iminium cation base peaks. RESULTS: These iminium cation base peaks show characteristic product ion spectra which allow differentiation of the side-chain propyl and isopropyl groups in the structure. The n-propyl side chain containing iminium cation base peak (m/z 126) in the EI-MS spectrum yields a major product ion at m/z 84 while the regioisomeric m/z 126 base peak for the isopropyl side chain yields a characteristic product ion at m/z 70. Deuterium labeling in both the pyrrolidine ring and the alkyl side chain confirmed the process for the formation of these major product ions. CONCLUSIONS: Product ion fragmentation provides useful data for differentiation of n-propyl and isopropyl side-chain iminium cations from cathinone derivative drugs of abuse. Regioisomeric n-propyl and isopropyl iminium cations of equal mass yield characteristic product ions identifying the alkyl side-chain regioisomers in the pyrrolidine cathinone derivatives. Copyright © 2016 John Wiley & Sons, Ltd.

Mass spectral studies on 1-n-pentyl-3-(1-naphthoyl)indole (JWH-018), three deuterium-labeled analogues and the inverse isomer 1-naphthoyl-3-n-pentylindole.

RATIONALE: A number of synthetic cannabinoids such as the 1-alkyl-3-acylindoles are the target of significant designer drug activity. One of the first waves of these compounds identified in clandestine samples was 1-n-pentyl-3-(1-naphthoyl)indole, JWH-018. These totally synthetic molecules can be prepared in a number of regioisomeric forms. METHODS: The electron ionization mass spectrometric (EI-MS) fragmentation of the 1-n-pentyl-3-(1-naphthoyl)indole is compared to its inverse isomer 1-naphthoyl-3-n-pentylindole. These two substances are directly available from indole using identical precursor reagents and similar reaction conditions. Stable isotope deuterium labeling of the three major regions of the JWH-018 molecule allows confirmation of the structures of the major fragment ions. The spectra for the 1-n-pentyl-3-(1-naphthoyl)-d(5) -indole, 1-n-pentyl-3-(1-d(7) -naphthoyl)indole and 1-d(11) -n-pentyl-3-(1-naphthoyl)indole provide significant assistance in elucidating the structures for the major fragment ions in JWH-018. RESULTS: The EI mass spectra for these isomers show a number of unique ions which allow for the differentiation of the 1-alkyl-3-acylindole compounds from the inverse regioisomeric 1-acyl-3-alkylindoles. The fragment ion [M-17](+) at m/z 324 for JWH-018 was formed by the elimination of a hydroxyl radical and the spectra of the three deuterium-labeled derivatives indicated the loss of hydrogen from the naphthalene ring. Further structural analogues suggest the hydrogen to come from the 8-position of the naphthalene ring. CONCLUSIONS: The three deuterium-labeled analogues provide significant assistance in confirming the structures for the major fragment ions in the mass spectrum of the traditional synthetic cannabinoid compound, 1-n-pentyl-3-(1-naphthoyl)indole, JWH-018. The 1-naphthoyl-3-n-pentylindole inverse regioisomer can be easily differentiated from the traditional synthetic cannabinoid compound.

GC-MS analysis of the regioisomeric methoxy- and methyl-benzoyl-1-pentylindoles: Isomeric synthetic cannabinoids.

The regioisomeric 1-n-pentyl-3-(methoxybenzoyl)indoles and the 1-n-pentyl-3-(methylbenzoyl)indoles represent potential designer modifications in the synthetic cannabinoid drug category. These six compounds were prepared by a two-step synthetic method. The analytical properties and methods of regioisomeric differentiation were developed in this study. The molecular ion represents the base peak in the EI mass spectra for most of the compounds in this group. The meta- and para-isomers in each series display fragment ions at equivalent masses with some differences in relative abundance of these ions. The ortho-substituted isomers for both the methoxybenzoyl and methylbenzoyl series show a unique fragment ion occurring at M-17. Deuterium labeling for the methoxy group in the ortho-methoxybenzoyl isomer (ortho-OCD3) confirmed the ortho-substituent as the source of the hydrogen in OH (M-17) elimination. The two sets of regioisomers were well resolved by capillary gas chromatography and the elution order reflected increasing molecular linearity. In both sets of compounds the ortho-isomer eluted first and the para-isomer showed the highest retention time. The HPLC separation showed the ortho-isomer eluting first and the meta-isomer eluting last in both sets of regioisomers.

Analytical differentiation of 1-alkyl-3-acylindoles and 1-acyl-3-alkylindoles: isomeric synthetic cannabinoids.

The 1-alkyl-3-acylindoles and the inverse regioisomeric 1-acyl-3-alkylindoles can be prepared directly from a common set of precursor materials and using similar synthetic strategies. The EI mass spectra for these isomers show a number of unique ions which allow for the differentiation of the 1-alkyl-3-acylindole compounds from the inverse regioisomeric 1-acyl-3-alkylindoles. The base peak at m/z 214 in the 1-n-pentyl-3-benzoylindole represents the M-77 cation fragment resulting from the loss of the phenyl group, and this ion is not observed in the inverse isomer. The 1-benzoyl-3-n-pentylindole inverse regioisomer shows a base peak at m/z 105 for the benzoyl cation. Thus, these two base peaks are the result of fragmentation initiated at the carbonyl-oxygen for both isomers. The 1-pentyl-3-benzoylindole is characterized by the strong intensity carbonyl band at 1703 cm(-1), while the amide carbonyl appears as a strong band of equal intensity at 1681 cm(-1) in the 1-benzoyl-3-pentyl regioisomer.

Synthesis and antinociceptive properties of N-phenyl-N-(1-(2-(thiophen-2-yl)ethyl)azepane-4-yl)propionamide in the mouse tail-flick and hot-plate tests.

The goals of this study, were to synthesize N-phenyl-N-(1-(2-(thiophen-2-yl)ethyl)azepane-4-yl)propionamide (1c) and determine its antinociceptive properties. The effect of clonidine on 1c antinociception and the involvement of opioid, α2-adrenergic, and I2 imidazoline receptors in 1c antinociception were studied. Also examined was the effect of an endothelin ETA receptor antagonist on 1c antinociception. Synthesis of 1c was accomplished in two steps using modifications of previously reported methods. Antinociceptive (tail-flick and hot-plate) latencies were measured in male Swiss Webster mice treated with 1c; antagonists+1c; clonidine+1c; or antagonists+clonidine+1c. Mice were pretreated with naloxone (opioid antagonist), yohimbine (α2-adrenoceptor antagonist), idazoxan (α2-adrenoceptor/I2-imidazoline antagonist), BU224 (I2-imidazoline antagonist) or BQ123 (endothelin ETA receptor antagonist) to study the involvement of these receptors. Compound 1c produced a dose-dependent increase in antinociceptive latencies; ED50 values were 0.15 mg/kg and 0.16 mg/kg, respectively, in the tail flick and hot plate tests. Naloxone, but not yohimbine, idazoxan or BU224, blocked 1c antinociception. Neither clonidine nor BQ123 potentiated 1c antinociception. Results demonstrate that 1c is 15-times more potent than morphine. The antinociceptive effect of 1c is mediated through opioid receptors. The α2-adrenergic, I2-imidazoline and endothelin ETA receptors are not involved in 1c antinociception.

Evaluate the in vitro effect of anthracycline and alkylating cytophosphane chemotherapeutics on dopaminergic neurons.

BACKGROUND: Iatrogenesis is an inevitable global threat to healthcare that drastically increases morbidity and mortality. Cancer is a fatal pathological condition that affects people of different ages, sexes, and races around the world. In addition to the detrimental cancer pathology, one of the most common contraindications and challenges observed in cancer patients is severe adverse drug effects and hypersensitivity reactions induced by chemotherapy. Chemotherapy-induced cognitive neurotoxicity is clinically referred to as Chemotherapy-induced cognitive impairment (CICI), chemobrain, or chemofog. In addition to CICI, chemotherapy also causes neuropsychiatric issues, mental disorders, hyperarousal states, and movement disorders. A synergistic chemotherapy regimen of Doxorubicin (Anthracycline-DOX) and Cyclophosphamide (Alkylating Cytophosphane-CPS) is indicated for the management of various cancers (breast cancer, lymphoma, and leukemia). Nevertheless, there are limited research studies on Doxorubicin and Cyclophosphamide's pharmacodynamic and toxicological effects on dopaminergic neuronal function. AIM: This study evaluated the dopaminergic neurotoxic effects of Doxorubicin and Cyclophosphamide. METHODS AND RESULTS: Doxorubicin and Cyclophosphamide were incubated with dopaminergic (N27) neurons. Neuronal viability was assessed using an MTT assay. The effect of Doxorubicin and Cyclophosphamide on various prooxidants, antioxidants, mitochondrial Complex-I & IV activities, and BAX expression were evaluated by Spectroscopic, Fluorometric, and RT-PCR methods, respectively. Prism-V software (La Jolla, CA, USA) was used for statistical analysis. Chemotherapeutics dose-dependently inhibited the proliferation of the dopaminergic neurons. The dopaminergic neurotoxic mechanism of Doxorubicin and Cyclophosphamide was attributed to a significant increase in prooxidants, a decrease in antioxidants, and augmented apoptosis without affecting mitochondrial function. CONCLUSION: This is one of the first reports that reveal Doxorubicin and Cyclophosphamide induce significant dopaminergic neurotoxicity. Thus, Chemotherapy-induced adverse drug reaction issues substantially persist during and after treatment and sometimes never be completely resolved clinically. Consequently, failure to adopt adequate patient care measures for cancer patients treated with certain chemotherapeutics might substantially raise the incidence of numerous movement disorders.

Gas chromatography/mass spectrometry analysis of the six-ring regioisomeric dimethoxybenzyl-N-methylpiperazines (DMBMPs).

RATIONALE: Piperazine-based designer drugs represent a novel class of substances found in illicit drug samples in the US and abroad. The clandestine production of these substances often makes use of piperazine as a key commercially available precursor substance. The commercial availability of 1-methylpiperazine suggests additional designer modification based on this additional precursor material. METHODS: This study focuses on the electron ionization mass spectrometric (EI-MS) fragmentation of the dimethoxybenzyl-N-methylpiperazines as potential designer modifications of the general benzylpiperazine drug skeleton and explores the gas chromatography (GC)/MS properties of all six of these regioisomeric substances. RESULTS: Fragmentation of the bond between the benzylic carbon and the adjacent piperazine nitrogen provides the base peak in all six spectra. The internal fragmentation within the piperazine ring produces a number of unique ions in the mass spectra of these dimethoxybenzyl-N-methylpiperazines. The migration of methyl groups from nitrogen and oxygen were confirmed by deuterium-labeling experiments. CONCLUSIONS: The six regioisomeric dimethoxybenzyl-N-methylpiperazines yield equivalent fragment ions and deuterium labeling confirmed the elemental composition of the characteristic fragments in their mass spectra. Mixtures of the dimethoxybenzyl-N-methylpiperazines were successfully resolved via capillary gas chromatography using a relatively polar stationary phase and temperature-programming conditions. Copyright © 2013 John Wiley & Sons, Ltd.

Critical Clinical Evaluation of COVID-19 Patients with Tuberculosis in the Indian Sub-Continent.

BACKGROUND: COVID-19 and tuberculosis (TB) are infectious diseases that predominantly affect the respiratory system with common symptoms, such as cough, fever, and shortness of breath, making them dual burdens. METHODS: This review will discuss the characteristics of the coexistence of TB and new infectious illnesses to provide a framework for addressing the current epidemic. Currently, there are no clear and significant data on COVID-19 infection in TB patients, they may not respond appropriately to drug therapy and may have worse treatment outcomes, especially if their TB treatment is interrupted. Due to emergence, measurements should be taken to minimize TB and COVID-19 transmission in communal settings and health care institutions were created. For both TB and COVID-19, accurate diagnostic testing and well-designed, and established therapeutic strategies are required for effective treatment. RESULTS: Several health care organizations and networks have specimen transit methods that can be utilized to diagnose and monitor the etiology and progression of COVID 19 and perform contact tracing in developed and underdeveloped nations. Furthermore, patients and health care programs could benefit from increased use of digital health technology, which could improve communication, counseling, treatment, and information management, along with other capabilities to improve health care. CONCLUSION: Patients with COVID-19 pulmonary/respiratory problems may seek treatment from respiratory physicians, pulmonologists, TB experts, and even primary health care workers. To have prophylactic and therapeutic strategies against COVID-19, TB patients should take the appropriate health care measures recommended by health care professionals/government officials and maintain their TB therapy as indicated.

Effects of developmental exposures to Bisphenol-A and Bisphenol-S on hepatocellular function in male Long-Evans rats.

Bisphenol-S (BPS) is a current substitute for Bisphenol-A (BPA) in various commercial products (paper, plastics, protective can-coatings, etc.) used by all age groups globally. The current literature indicates that a drastic surge in pro-oxidants, pro-apoptotic, and pro-inflammatory biomarkers in combination with diminished mitochondrial activity can potentially decrease hepatic function leading to morbidity and mortality. Consequently, there are increasing public health concerns that substantial Bisphenol-mediated effects may impact hepatocellular functions, particularly in newborns exposed to BPA and BPS postnatally. However, the acute postnatal impact of BPA and BPS and the molecular mechanisms affecting hepatocellular functions are unknown. Therefore, the current study investigated the acute postnatal effect of BPA and BPS on the biomarkers of hepatocellular functions, including oxidative stress, inflammation, apoptosis, and mitochondrial activity in male Long-Evans rats. BPA and BPS (5 and 20 microgram/Liter (µg/L) of drinking water) were administered to 21-day-old male rats for 14 days. BPS had no significant effect on apoptosis, inflammation, and mitochondrial function but significantly reduced the reactive oxygen species (51-60 %, **p < 0.01) and nitrite content (36 %, *p < 0.05), exhibiting hepatoprotective effects. As expected, based on the current scientific literature, BPA induced significant hepatoxicity, as seen by significant glutathione depletion (50 %, *p < 0.05). The in-silico analysis indicated that BPS is effectively absorbed in the gastrointestinal tract without crossing the blood-brain barrier (whereas BPA crosses the blood-brain barrier) and is not a substrate of p-Glycoprotein and Cytochrome P450 enzymes. Thus, the current in-silico and in vivo findings revealed that acute postnatal exposure to BPS had no significant hepatotoxicity.

Studies on the formation of N-methylperfluoroalkylnitrile cations from perfluoroacylphenethylamines in electron ionisation mass spectrometry: unique marker ion fragments in methamphetamine analysis.

The mass spectra of the perfluoroacyl derivatives of methamphetamine show a unique and characteristic fragment ion identified as the N-methylperfluoroalkylnitrile cation (C(n)F(2n+1)CNCH(3))(+). This ion appears at various m/z values depending on the nature of the perfluoroacyl species and is generated via rearrangement of the perfluoroacyl immonium fragment formed by loss of the benzyl-radical from the molecular ion. Analogous ions have been described in the mass spectra of other methamphetamine-like side chain substances regardless of the aromatic ring substitution pattern. The scope and limitation of this rearrangement pathway were evaluated in this study by preparing a set of substituted phenethylamines and related compounds of varying structure. The perfluoroacyl moiety leads to the formation of the highest abundance of the N-methyl nitrile cation fragment while hydrocarbon acyl groups do not show the N-methylnitrile cation as a significant peak. The N-methyl group is required for the formation of the N-methyl nitrile cation and higher N-alkyl homologues eliminate the corresponding alkene species from the acyl immonium fragment. The loss of benzaldehyde and acetone from the perfluoroacylimmonium species produces the highest relative abundance of the unique N- methylperfluoroalkylnitrile cation.

Impact of COVID-19 therapy on hyperglycemia.

The goal of this study was to analyze the effect of COVID-19 drugs and biologicals on hyperglycemia. A literature search with key terms, such as "COVID-19 drugs and hyperglycemia" and "COVID-19 vaccines and hyperglycemia," was conducted using PubMed through September 2021. The CDC data were referenced for current COVID-19 profile and statistics. The NIH COVID-19 guidelines were referenced for updated treatment recommendations. Micromedex and UpToDate were used for drug and disease information. Current results suggested that corticosteroids (dexamethasone), remdesivir and antivirals (lopinavir and ritonavir) all have the potential to significantly raise blood glucose levels putting patients at elevated risk for severe complications. In contrary, hydroxychloroquine is associated with hypoglycemia, and tocilizumab decreases inflammation which is associated with improving glucose levels. Other anti-cytokine bioactive molecules are correlated with lower blood glucose in patients with and without diabetes mellitus. Ivermectin, used for mild COVID-19 disease, possesses the potential for lowering blood glucose. Covishield, Pfizer-BioNTech, and Moderna have all been associated with hyperglycemia after the first dose. Individualized /personalized patient care is required for diabetic mellitus patients with COVID-19 infection. Improper drug therapy aggravates hyperglycemic conditions and other comorbid conditions, leading to increased morbidity and mortality.

GC and mass spectral studies on acylated side chain regioisomers of 3-methoxy-4-methyl-phenethylamine and 4-methoxy-3-methyl-phenethylamine.

The side chain regioiomers of the 3-methoxy-4-methylphenethylamines and 4-methoxy-3-methyl-phenethylamines have mass spectra essentially equivalent to the controlled drug substance 3,4-methylenedioxymethamphetamine (3,4-MDMA), all have molecular weight of 193 and major fragment ions in their electron ionization mass spectra at m/z 58 and 135/136. Furthermore, the compounds in this study have ring substitutions in the same relative positions as 3,4-MDMA. The nonequivalence of the substituents (methoxy and methyl) yields two sets of compounds, 3-methoxy-4-methyl- and 4-methoxy-3-methylphenethylamines. The perfluoroacyl derivatives (pentafluoropropionylamides and heptafluorobutrylamides) of the primary and secondary regioisomeric amines were prepared and evaluated in gas chromatography-mass spectrometry studies. The mass spectra for these derivatives are significantly individualized and the resulting unique fragment ions allow for specific side chain identification. The heptafluorobutrylamide derivatives offer more fragment ions than the pentafluoropropionylamides for molecular individualization among these regioisomeric substances. These acylated derivatives show excellent resolution on a dimethyl polysiloxane stationary phase such as Rtx-1.

GC-MS evaluation of a series of acylated derivatives of 3,4-methylenedioxymethamphetamine.

A series of acylated derivatives of 3,4-methylenedioxy-methamphetamine (3,4-MDMA) are prepared and evaluated in gas chromatography-mass spectrometry (GC-MS) studies. The perfluoroalkyl amides of 3,4-MDMA show the lowest GC retention, while the aromatic amides such as the benzamide show the greatest retention on the dimethylpolysiloxane stationary phase (Rtx-1). The mass spectral properties of the acetyl, propionyl, and butyryl derivatives all show a base peak at m/z 58 which is the base peak for the underivatized 3,4-MDMA. All acylated derivatives provide mass spectral information (m/z 162) to identify the three-carbon side chain for 3,4-MDMA. The perfluoroalkyl amides yield several unique mass spectral fragments for specific identification of 3,4-MDMA. MS fragmentation pathways are illustrated and validated using analogous deuterated derivatives. A combination of excellent chromatographic properties and unique mass spectral fragments allows the perfluoroalkyl amides to provide maximum specific structural information in the GC-MS analysis of 3,4-MDMA.

Gas Chromatography-Mass Spectrometry (GC-MS) and Gas Chromatography-Infrared (GC-IR) Analyses of the Chloro-1- n-pentyl-3-(1-naphthoyl)-Indoles: Regioisomeric Cannabinoids.

The analytical differentiation of the indole ring regioisomeric chloro-1- n-pentyl-3-(1-naphthoyl)-indoles is described in this report. The regioisomeric chloroindole precursor compounds, N- n-pentyl chloroindole synthetic intermediates, and the target chloro-substituted naphthoylindoles showed the equivalent gas chromatographic elution order based on the position of chlorine substitution on the indole ring. The regioisomeric chloro-1- n-pentyl-3-(1-naphthoyl)-indoles yield electron ionization mass spectra having equivalent major fragments resulting from cleavage of the groups attached to the central indole nucleus. Fragment ions occur at m/z 127 and 155 for the naphthyl and naphthoyl cations common to all indoles having the naphthoyl group substituted at the indole-3 position. Fragments resulting from the loss of the naphthoyl and/or n-pentyl groups from the molecular radical cation yield the cations at m/z 318, 304, 248, and 178. The characteristic (M-17)+ fragment ion at m/z 358 resulting from the loss of OH radical is significant in the mass spectra of all these compounds with 1-naphthoyl groups substituted at the indole-3 position. The vapor phase infrared spectra provide a number of characteristic absorption bands to identify the individual isomers.

GC-MS analysis of ring and side chain regioisomers of ethoxyphenethylamines.

Mass spectral differentiation of 3,4-methylenedioxymethamphetamine (3,4-MDMA), a controlled drug, and its 2,3-regioisomer from the ring substituted ethoxyphenethylamines is possible after formation of the perfluoroacyl derivatives, pentafluoropropionamides (PFPA), and heptafluorobutyrylamides (HFBA). The ring substituted ethoxyphenethylamines constitute a unique set of compounds having an isobaric relationship with 3,4-MDMA. These isomeric forms of the 2-, 3-, and 4-ethoxy phenethylamines have mass spectra essentially equivalent to 3,4-MDMA; all have molecular weight of 193 and major fragment ions in their electron ionization mass spectra at m/z 58 and 135/136. All the side chain regioisomers of 2-ethoxy phenethylamine having equivalent mass spectra to 3,4-MDMA are synthesized and compared via gas chromatography-mass spectrometry to 2,3- and 3,4-methylenedioxymethamphetamine. The mass spectra for the perfluoroacyl derivatives of the primary and secondary amine regioisomers are significantly individualized, and the side chain regioisomers yield unique hydrocarbon fragment ions at m/z 148, 162, and 176. Additionally, the substituted ethoxymethamphetamines are distinguished from the methylenedioxymethamphet-amines via the presence of the m/z 107 ion. Gas chromatographic separation on relatively non-polar stationary phases successfully resolves these derivatives.

GC-MS analysis of acylated derivatives of a series of side chain regioisomers of 2-methoxy-4-methyl-phenethylamines.

Five side chain regioisomers of 2-methoxy-4-methylphenethylamine constitute a unique set of compounds having an isobaric relationship with the controlled drug substance 3,4-methylenedioxymethamphetamine (3,4-MDMA or Ecstasy). These isomeric forms of the 2-methoxy-4-methyl-phenethylamines have mass spectra essentially equivalent to 3,4-MDMA; all have molecular weight of 193 and major fragment ions in their electron ionization mass spectra at m/z 58 and 135/136. Mass spectral differentiation of 2,3 and 3,4-MDMA from primary and secondary amine regioisomeric side chains of 2-methoxy-4-methyl-phenethylamines was possible after formation of the perfluoroacyl derivatives, pentafluoropropionamides (PFPA) and heptafluorobutyrylamides (HFBA). The mass spectra for these derivatives are individualized and the resulting unique fragment ions allow for specific side-chain identification. The individualization is the result of fragmentation of the alkyl carbon-nitrogen bond yielding unique hydrocarbon fragments of varying mass. Gas chromatographic separation on relatively non-polar stationary phases gave essentially base line resolution for these compounds.