Evaluation of ACD/1D and 2D NMR Processors Running on a Mac

Paul Sigala, Dept. of Biochemistry, Stanford University, Graduate Student (Ph.D Candidate)

This review is to evaluate the performance of ACD/1D and 2D NMR Processors (v. 9.0) running on a Macintosh laptop computer using a simulated Windows PC environment. The computer is a Macintosh PowerPC G4 laptop equipped with a 1.5 GHz processor and 768 MB of RAM, and running OS 10.3.9. Microsoft Virtual PC for Mac version 7.0.1 and Microsoft Windows XP were installed to create a simulated Windows environment for running the ACD/Labs NMR Processors. The ACD/Labs software was evaluated using either 256 or 520 MB of RAM allocated to Virtual PC. Prior to acquiring the ACD/Labs software, I evaluated multiple 1D NMR processing programs running within native Macintosh environments and found none to have either the range of features, or ease of use of the ACD/1D and 2D NMR Processors.

My primary motivation in acquiring and using the ACD/Labs software was to have the freedom and portability to process and analyze various types of NMR experimental data, as well as manipulate and render spectra into a format for making publication-quality figures on my personal laptop computer. With the ACD/Labs software, I can now process and manipulate spectra at my desk, at home, or while traveling. Furthermore, both the 1D and 2D NMR Processors have features that go beyond the limitations in other processing software. For example, the peak-fitting function of the 1D Processor has been essential in my work to fit lineshapes for poorly shaped exchange-broadened resonances, both for deconvoluting overlapping resonances, as well as fitting and comparing peak areas. The ability to immediately edit spectra within ACD/ChemSketch for easy future import into other graphical editors (Adobe Illustrator, etc.) is of additional convenience. Both the 1D and 2D Processors appeared to function fully in the Virtual PC environment without issue. Since Virtual PC can run in 'full-screen' mode, ACD/Labs software use is seamless once Virtual PC and Windows XP are running. All software features described in the manual for each processor worked successfully. For the 1D Processor, this includes transformation and apodization of Varian *.fid files, phase and baseline correction of protein spectra acquired with binomial water suppression and extensive baseline roll, peak picking and deconvolution, and lineshape analysis to analyze peak areas. For the 2D Processor, this included transformation of protein N-H HSQC spectra, adjustment of contour intervals and thresholds, referencing, and peak picking, assignment annotation, and integration of peak volumes for export and analysis in other programs. No apparent software problems were encountered while running the 1D or 2D Processors, however one minor glitch involves the need to periodically re-enter the license keys in register.exe.

While the ACD/Labs software performed fully within the Virtual PC Windows XP environment, it did appear to run more slowly in comparison to Macintosh programs running within the native Mac OSX environment. This is particularly noticeable during lineshape analysis and is presumably a function of Virtual PC performance and not the ACD/Labs software per se. Allocating more RAM (512 rather than the default 256 MB) to Virtual PC did improve the speed of the ACD/Labs Processors. Despite the somewhat reduced speed, use of the ACD/Labs software within Virtual PC was otherwise facile. For example, Virtual PC could be run in 'windowed mode' which allows for ready dialog and file 'dragging and dropping' between the Windows and Mac environments.

In general, the ACD/Labs software has been invaluable for viewing and processing spectra away from the instrument. The 1D Processor, in particular, is the most user-friendly software of its kind encountered to date. Evaluation of many other potential 1D processing programs installed on a native Mac platform proved to be slow and difficult to use. The ACD/Labs software, while not made to run in a native Mac environment, becomes a viable and appealing option once Virtual PC is installed. The slightly slowed performance and delay in starting/storing Virtual PC is more than off-set by the ease of use and convenience of the ACD/Labs Processors. While other fully-featured and easy-to-use 2D processing software (such as Sparky) are available that can run within the Mac environment, the ACD/2D NMR Processor provides a convenient and user-friendly alternative with the advantage of interfacing easily with the 1D software.

Using a Virtual Machine to Run ACD/Labs NMR Processors on a Mac

Jed Fisher, Faculty Professional Specialist, Chemistry and Biochemistry, University of Notre Dame

I acquired a MacBook Pro (2 GHz processor, 1 GB RAM), and used Parallels Desktop to install a Windows XP 2002 Pro virtual machine. Other than the 512 MB Ram upgrade, this is an "entry level" Mac.

I was not able to open all of the ACD/Labs modules simultaneously, which appears to be a limitation of Parallels rather than of the ACD/Labs software. When opened separately, each opened and ran flawlessly and otherwise my report to you is one word.

Wow.

I experienced only one "crash", on an attempt to clean a structure in ACD/ChemSketch; however, closing and restarting the virtual Windows desktop is quick and the loss of data in this one crash was inconsequential. Several previous (and subsequent) cleanings did not cause the crash. The only "bug" encountered concerns the Mac keyboard "delete" key not being recognized. The user must use the menu pull-down instead.

I did not attempt to download the ACD/Labs update, since my virtual Windows had neither Firewall nor Virus protection. I mention this only because this limitation—can't implement updates—is mentioned with some regularity on discussion boards concerning Parallels. I executed the *.exe ACD/Labs installation file by creating a Disk Image of the ACD/Labs files (using the utility that Parallels provides for this purpose), and opening this disk image within Windows. This might be the preferred way for handling Mac updating.

With the price of Macs in a seeming freefall, I can't believe that any Mac user who wants top-end desktop ACD/Labs performance will balk at using Parallels/Windows to do so. The most difficult aspect of my using ACD/Labs software on the Mac was adjusting to the Windows interface. Using the ACD/Labs NMR software was easy, and using ChemSketch just less so (the program is too busy for my taste).

Everything that I've done so far on this Mac using the ACD/Labs modules (1D and 2D NMR Processor) occurs at breathtaking speed, calculating—almost instantaneously—a 2D COSY and HSQC each took less than 10 seconds). I spent more time keyboarding in the file, naming and saving, than the machine does computing.