Molecular Design of Potential Triple-Action Antibacterial Agents and Related Pro-Drugs

 บทคัดย่อ การเพิ่มขึ้นของเชื้อแบคทีเรียดื้อยาที่ก่อโรคในมนุษย์เป็นปัญหาด้านสุขภาพทั่วโลก ความท้าทายในการแก้ปัญหานี้ทำให้มีการเพิ่มความพยายามในการวิจัยแบบสหสาขาวิชามากขึ้น หนึ่งในความพยายามนั้นคือการพัฒนาโมเลกุลของสารยับยั้งเชื้อแบคทีเรียดื้อยาให้มีการออกฤทธิ์ยับยั้งเชื้อได้มากกว่าหนึ่งเป้าหมายในเซลล์ของแบคทีเรีย บทความนี้ได้กล่าวครอบคลุมถึงสิ่งที่ต้องพิจารณาในการออกแบบโมเลกุล   ความเป็นไปได้ในการสังเคราะห์สารยับยั้งเชื้อแบคทีเรียที่ในโมเลกุลเดียวกันสามารถเกิดอันตรกิริยากับเป้าหมายในเซลล์ของแบคทีเรียได้ถึงสามเป้าหมายและออกฤทธิ์ร่วมกันอย่างมีประสิทธิภาพในการยับยั้งเชื้อแบคทีเรีย และกล่าวถึงสารโปร-ดรักส์ของสารยับยั้งเชื้อแบคทีเรียดังกล่าว โดยเฉพาะอย่างยิ่งการออกแบบและการสังเคราะห์สารยับยั้งเชื้อแบคทีเรียที่มีโครงสร้างของสารอัลคาลอยด์เบอร์เบอรีนเป็นองค์ประกอบ  - - - Molecular Design of Potential Triple-Action Antibacterial Agents and Related Pro-DrugsABSTRACT Increasing antibiotic resistance by human pathogenic bacteria is a global health concern.  This health challenge calls for increased multi-disciplinary research efforts to address the issue and one such effort is concerned with the development of novel single molecule agents with more than one bacterial target site for action or interaction. This review covers molecular design considerations and some possible synthetic molecular entities for potential triple-action antibacterial agents and related pro-drugs, particularly those based on the quaternary alkaloid berberine

Synthetic Approaches to Nuclearly-Modified Cephalosporin Antibiotics

Synthetic routes to a 1-hydroxy-1-carbacephem (1), by structure-activity considerations an analogue of potential antibiotic activity, are described. Synthesis of a substituted pyridine for reduction to a cyclic enamine and subsequent annellation to a B-lactam were not successful. An acyclic inline precursor of (1) was prepared but did not yield a beta-lactam by an established annellation procedure. Approaches to a cyclic amine potentially convertible into (1) are described

Biosorption of lac dye by the red marine alga Gracilaria tenuistipitata: biosorption kinetics, isotherms, and thermodynamic parameters

The hypothesis that the dried, ground biomass of the red marine alga Gracilaria tenuistipitata could be used for the efficient removal of lac dye from aqueous solution was assessed in this work. The effects of parameters such as initial pH, biosorbent dosage, contact time, initial dye concentration, and temperature on the biosorption capacity of the dye were investigated. Equilibrium data were analysed using Langmuir, Freundlich, and Temkin isotherm models, and the Freundlich model provided the highest coefficient of determination values. Biosorption kinetic data were successfully described with a pseudo-second-order model at initial dye concentrations of 50, 80, 100, and 120 mg l−1. The thermodynamic parameters of biosorption - enthalpy change (∆H° = −30.64 kJ mol−1), free energy change (∆G° = 4.32 kJ mol−1 at 303 K to 7.78 kJ mol−1 at 333 K), and entropy change (∆S° = −115.38 J mol−1 K−1) - were determined. The negative value of the enthalpy change and positive values of the free energy change indicate that the biosorption process is exothermic and non-spontaneous. The negative value of the entropy change is consistent with decreased randomness at the solid-liquid interface with dye biosorption. Attenuated total reflectance-Fourier transform infrared spectroscopic analysis confirmed the presence of lac dye on the G. tenuistipitata material. The efficiency of lac dye removal by this biomass material at 20 g l−1 and with an initial dye concentration of 50 mg l−1 in acidic solution was 71%, which indicated its potential usefulness as a new dye biosorbent

The Flavonoids of Orophea polycarpa A. DC. (Annonaceae)

Investigation on the neutral fraction of the leaves of Oraphea polycarpa A. DC. led to the isolation of two flavonoids identified as 2'-hydroxy-4,4',6'trimethoxychalcone and 5,7,4'-trimethoxyflavanone

SYNTHESIS OF THE ISOQUINO-[2,1-c][1,3]-BENZODIAZEPINE DERIVATIVE FROM PAPAVERINE

The objective of this research was to synthesize isoquino[2,1-c][1,3]benzodiazepine from papaverine alkaloid. Functional Group Interconversion (FGI) and Carbon -Nitrogen bond connection approach was investigated. Papaverine (1) was nitrated by HNO3 to compound (2) and followed by reduction with Sn and HCl to afford aminonorlaudanosine (3). Formation of cyclic benzodiazepine (4) was achieved by reaction of (3) with CS2. Products of reactions were confirmed by Nuclear Magnetic Resonances (n.m.r), Mass Spectrum, and Fourier Transform Infra Red (FTIR).   Keywords: isoquino[2,1-c][1,3]benzodiazepine, papaverin

Taking a Person-Centered Approach to Personality: A Latent-Profile Analysis of the HEXACO Model of Personality

Our study applies a person-centered approach to the HEXACO model of personality using latent profile analysis (LPA). While the traditional variable-centered approach assumes that the relations among variables within a population are homogenous, the person-centered approach identifies subgroups within samples that have similar scores on several variables of interest, in this case, the six factors of personality. Data from two independent samples were collected at a large North American university. The results of LPA revealed five distinct and interpretable profiles that replicated and were found to be consistent across both samples. We discuss how our findings attest to the meaningfulness of personality profiles, and suggest additional ways in which a person-centered approach might be applied in personality research

Additive effects on cotton dyeing with dye extract from achiote seeds

466-474Cotton yarns have been pretreated with the additives, such as chitosan, microcrystalline chitosan, quaternized chitosan & aqueous extract from the fruit of Diospyros mollis Griff, as well as with the commercial formaldehyde-free cationic fixing agent (Sera® Fast C-NC) & alum (post-mordanting), and their dyeing fastness properties are studied. These treated cotton yarns are then dyed with the annatto dye extract from Bixa orellana L. (Achiote) seeds and tested for different properties including K/S value, light fastness, and wash fastness. Pre-treatment of cotton yarn with chitosan or microcrystalline chitosan solution (together with glyoxal cross-linking) or quaternized chitosan, or Sera® Fast C-NC before dyeing, shows a better color depth (K/S) and improved wash fastness properties in comparison to yarn with alum post-mordanting and the untreated cotton yarn. Improved light fastness is also obtained on inclusion of the anti-oxidant ascorbic acid in the post-treatment protocol. These additive treatments thus offer considerable potential for the improved annatto dyeing of cotton

A convenient and efficient synthesis of (S)-lysine and (S)-arginine homologues via olefin cross-metathesis

A convenient five step synthesis of (S)-homolysine, incorporating a key olefin cross-metathesis step in the chain extension methodology, has been developed, together with a six step related synthesis of a new homologue of arginine, (S)-bishomoarginine