Although initial interest in science, technology, engineering and mathematics (STEM) is high, recruitment and retention remains a challenge, and some populations are disproportionately underrepresented in STEM fields. To address these challenges, the Microbiology and Cell Science Department in the College of Agricultural and Life Sciences at the University of Florida has developed an innovative 2+2 degree program. Typical 2+2 programs begin with a student earning an associate’s degree at a local community college and then transferring to a 4-year institution to complete a bachelor’s degree. However, many universities in the United States, particularly land-grant universities, are located in rural regions that are distantly located from their respective states’ highly populated urban centers. This geographical and cultural distance could be an impediment to recruiting otherwise highly qualified and diverse students. Here, a new model of a 2+2 program is described that uses distance education as the vehicle to bring a research-intensive university’s life sciences curriculum to students rather than the oft-tried model of a university attempting to recruit underrepresented minority students to its location. In this paradigm, community college graduates transfer into the Microbiology and Cell Science program as distance education students to complete their Bachelor of Science degree. The distance education students’ experiences are similar to the on-campus students’ experiences in that both groups of students take the same department courses taught by the same instructors, take required laboratory courses in a face-to-face format, take only proctored exams, and have the same availability to instructors. Data suggests that a hybrid online transfer program may be a viable approach to increasing STEM participation (as defined by enrollment) and diversity. This approach is particularly compelling as the distance education cohort has comparable grade point averages and retention rates compared to the corresponding on-campus transfer cohort.

Radical-mediated thiodesulfonylation of the vinyl and (α-fluoro)vinyl sulfones, derived from aldehydes and ketones, with aryl thiols in organic or aqueous medium provided access to vinyl and (α-fluoro)vinyl sulfides. The vinyl sulfides were formed predominantly with E stereochemistry independent of the stereochemistry of the starting vinyl sulfones. KeywordsFluoroalkenes; Radical reactions; Vinyl sulfides; α-Fluoro vinyl sulfides; Vinyl sulfones Vinyl sulfides are valuable tools in organic synthesis and are used as enolate ion equivalents, 1 as components of [2+2] cyclo-additions, 2 and as substrates in transition metal catalyzed carbon-carbon bond forming reactions.3 Methods for the synthesis of 1-alkenyl sulfides include Wittig reaction,4 ionic and radical additions of thiols to alkynes,5 coupling of 1-alkenyl halides with thiols, 6-9 and transition metal catalyzed anti-Markovnikov hydrothiolation 9-12 of alkynes with arenethiols and alkanethiols to produce E isomers, including hydrothiolation in water medium. 13 Vinyl sulfonium ions, generated via the biological methylation of the corresponding vinyl sulfides act as inhibitors of thioether S-methyltransferase 14 and proteolytic enzyme papain. 15 They are highly reactive towards nucleophiles and bind covalently to DNA, RNA and proteins in vivo. 16 Moreover, vinyl sulfonium salts are more electrophilic than the corresponding vinyl sulfones, which are known for their ability to inhibit cysteine proteases. 17,18 The (α-halo)vinyl sulfides can be prepared by Wittig-Horner reactions with diethyl chloro (phenylthio)-methanephosphonate 19 or by addition of the hydrogen halides (HI, HBr and HCl) to acetylenic sulfides (chalcogenides).20 The regioselectivity and stereoselectivity of such additions were improved when equivalent quantities of hydrogen halide, generated in situ from trimethylsilyl halides and anhydrous methanol, were utilized 21 instead of excess aqueous HX or saturated gaseous HX in benzene. The (α-halo)vinyl sulfides have been employed in Stille, 21, Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Herein, we report stereoselective radical-mediated thiodesulfonylations of vinyl and (α-fluoro) vinyl sulfones with aryl thiols to provide access to vinyl and (α-fluoro)vinyl sulfides. Such thiodesulfonylation provides a flexible alternative to the hydrothiolation of alkynes with thiols under radical or metal catalysis conditions. It also offers convenient preparations of (α-fluoro) vinyl sulfides -a class of interesting fluoroalkenes which remain unexplored. 34 The thiodesulfonylation can be also viewed as re...

Moffatt oxidation of 2',3'-O-isopropylideneuridine (1a) and treatment of the crude 5'-aldehyde with formylmethylene-stabilized Wittig reagent gave the vinylogously extended 7'-aldehyde2a. Condensation of 2a with ethoxycarbonyl- or dibromomethylene phosphorane reagents gave the conjugated dienes 6a and 4a, respectively. Deacetonization gave diene ester 7a [5'(E),7'(E); with s-trans conformation] and dibromodiene 5a [5'(E)], respectively. Analogously, 2',3'-O-isopropylideneadenosine (1b) was Wittig-extended into the conjugated dibromodiene 5b [5'(E)] and dienoic ester 7b [5'(E),7'(E)]. Furthermore, palladium-catalyzed coupling of the vinyl 6'(E)-stannanes 14 with (E) and (Z) ethyl 3-iodoacrylate gave stereodefined access to dienoic esters 7 (E,E) and 16 (E,Z). Incubation of AdoHcy hydrolase with 100 microM of 5b resulted in partial inhibition of the enzyme without any apparent change in the enzyme's nicotinamide adenine dinucleoside (NAD(+)) content. In contrast, 7b and 16b produced time- and concentration-dependent inactivation of S-adenosyl-L-homocysteine (AdoHcy) hydrolase producing significant decreases in the enzyme's NAD(+) content. However, 7b and 16b upon incubation with AdoHcy hydrolase were not metabolized suggesting that these compounds are type I mechanism-based inhibitors. No specific antiviral activity was noted for 5a,b, 7a,b, and 16a,b against any of the viruses tested; dibromodiene 5b proved cytotoxic at a concentration > or =6.7 microM and cytostatic at > or =11 microM, while dienoic esters 16a,b showed activity against both varicella-zoster virus (at 10 microM, 16a) and cytomegalovirus (at 10 microM, 16a; 18 microM, 16b).